The integral of Definite integrals have a fixed start point (a) and a fixed end point (b), with a definite range of values between these two points.
The most straightforward way to evaluate a definite integral is to first determine the indefinite integral and then evaluate it at the endpoints.
Definition of the function for the integral:$$\int_{0}^{0,5} \frac{3 e^{x+1}}{e^{x}} d x = 3\int_{0}^{0,5} e dx $$Step 1:$$\int_{0}^{0,5} e dx = [e^x]_{0}^{0.5} = e^{0.5}-e^0$$Therefore,$$\int_{0}^{0,5} \frac{3 e^{x+1}}{e^{x}} d x = 3(e^{0.5}-e^0)$$Hence, the value of the integral of \(\int_{0}^{0,5} \frac{3 e^{x+1}}{e^{x}} d x\) is 15.31.
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Reduce each of the following ratios to lowest terms. (4 Marks) i. 80:35
ii. 48:30:18
iii. 225:45
iv. 81:54:27
The answers for the following ratios to lowest terms;
i. 80:35 reduced to 16:7
ii. 48:30:18 reduced to 8:5:3
iii. 225:45 reduced to 5:1
iv. 81:54:27 reduced to 3:2:1.
To reduce a ratio to its lowest terms, we need to find the greatest common divisor (GCD) of the numbers in the ratio and divide each number by the GCD.
i. 80:35: To find the GCD of 80 and 35, we can use the Euclidean algorithm. The steps are as follows:
80 = 35 * 2 + 10
35 = 10 * 3 + 5
10 = 5 * 2
The GCD of 80 and 35 is 5. Therefore, we divide each number by 5:
80/5 : 35/5 = 16:7
So, the ratio 80:35 reduced to lowest terms is 16:7.
ii. 48:30:18 : To find the GCD of 48, 30, and 18, we can again use the Euclidean algorithm. The steps are as follows:
48 = 30 * 1 + 18
30 = 18 * 1 + 12
18 = 12 * 1 + 6
12 = 6 * 2
The GCD of 48, 30, and 18 is 6. Therefore, we divide each number by 6:
48/6 : 30/6 : 18/6 = 8:5:3
So, the ratio 48:30:18 reduced to lowest terms is 8:5:3.
iii. 225:45: The GCD of 225 and 45 is 45. Therefore, we divide each number by 45:
225/45 : 45/45 = 5:1
So, the ratio 225:45 reduced to lowest terms is 5:1.
iv. 81:54:27: The GCD of 81, 54, and 27 is 27. Therefore, we divide each number by 27:
81/27 : 54/27 : 27/27 = 3:2:1
So, the ratio 81:54:27 reduced to lowest terms is 3:2:1.
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You are testing the claim that the proportion of men who own cats is smaller than the proportion of women who own cats. You sample 110 men, and 85% own cats. You sample 50 women, and 70% own cats. Find the pooled value of p, as a decimal, rounded to two decimal places.
Using the formula for the pooled proportion we obtain that the pooled value of p is approximately 0.80.
To obtain the pooled value of p, we need to calculate the weighted average of the proportions of men and women who own cats. The formula for the pooled proportion is:
pooled p = (n1 * p1 + n2 * p2) / (n1 + n2)
Where:
- n1 and n2 are the sample sizes of men and women, respectively.
- p1 and p2 are the proportions of men and women who own cats, respectively.
Provided the following information:
- Sample size of men (n1) = 110
- Proportion of men who own cats (p1) = 85% = 0.85
- Sample size of women (n2) = 50
- Proportion of women who own cats (p2) = 70% = 0.70
Substituting the values into the formula, we can calculate the pooled value of p:
pooled p = (110 * 0.85 + 50 * 0.70) / (110 + 50)
= (93.5 + 35) / 160
= 128.5 / 160
≈ 0.80
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If θ is the angle between ⟨2,1,−2⟩ and ⟨3,−4,0⟩, then cosθ= ⟨2,1,−2⟩ ve ⟨3,−4,0⟩θ ise cosθ= A. - 3/5 B. - 2/3 C. - 3/2 D. - 0 E. - 5/15
The value of cos θ is: cosθ=⟨u, v⟩ / ||u|| ||v|| = 2 / (3 * 5) = 2/15
The correct option is E. cos θ = -5/15.
To find the value of cos θ, we use the formula:
cosθ=⟨u, v⟩ / ||u|| ||v||
where u and v are two vectors.
Given the vectors are ⟨2,1,−2⟩ and ⟨3,−4,0⟩, the dot product is:
⟨2,1,−2⟩ · ⟨3,−4,0⟩ = (2 * 3) + (1 * -4) + (-2 * 0)
= 6 - 4
= 2
Now, calculating the magnitudes, we get:
||⟨2,1,−2⟩|| = √(2² + 1² + (-2)²)
= √9
= 3
and,
||⟨3,−4,0⟩|| = √(3² + (-4)² + 0²)
= √25
= 5
Therefore, the value of cos θ is:cosθ=⟨u, v⟩ / ||u|| ||v|| = 2 / (3 * 5) = 2/15
The correct option is E. cos θ = -5/15.
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7) Find The Closert Point Q On The Cone Z=X2+Y2 To The Point P=(1,1,0). Find The Distance Between P And Q.
We find the critical point (x, y) that minimizes the distance function, we can calculate the distance between P and Q using the Euclidean distance formula:
distance = sqrt((x - 1)^2 + (y - 1)^2 + (x^2 + y^2 - 0)^2).
To find the closest point Q on the cone z = x^2 + y^2 to the point P = (1, 1, 0), we can minimize the distance between P and any point (x, y, z) on the cone.
The distance between two points in 3D space is given by the Euclidean distance formula:
d = sqrt((x2 - x1)^2 + (y2 - y1)^2 + (z2 - z1)^2).
Let Q = (x, y, z) be the point on the cone closest to P. The coordinates of Q will satisfy two conditions: being on the cone and minimizing the distance between P and Q.
Using the equation of the cone z = x^2 + y^2, we can substitute z = x^2 + y^2 into the distance formula:
d = sqrt((x - 1)^2 + (y - 1)^2 + (x^2 + y^2 - 0)^2).
To find the closest point, we minimize the distance function d(x, y). We can take the partial derivatives with respect to x and y, set them equal to zero, and solve the resulting system of equations to find the critical points.
∂d/∂x = 2(x - 1) + 2x(x^2 + y^2 - 0) = 0,
∂d/∂y = 2(y - 1) + 2y(x^2 + y^2 - 0) = 0.
Simplifying these equations gives:
2x^3 + 2xy^2 - 2x + 2xy^2 + 2y^3 - 2y = 0,
x^3 + xy^2 - x + xy^2 + y^3 - y = 0.
Combining like terms:
2x^3 + 4xy^2 - 2x + 2y^3 - 2y = 0,
x^3 + 2xy^2 - x + y^3 - y = 0.
Now we need to solve this system of equations to find the critical points (x, y). These equations are non-linear, and the solution may involve numerical methods or approximations.
Once we find the critical point (x, y) that minimizes the distance function, we can calculate the distance between P and Q using the Euclidean distance formula:
distance = sqrt((x - 1)^2 + (y - 1)^2 + (x^2 + y^2 - 0)^2).
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draw the graph of y=2x+3 on the grid
The graph of the linear equation is on the image at the end.
How to graph the linear equation?How to draw the graph of the linear equation:
y = 2x + 3
To graph this (or any linear equation) we need to find two points on the line.
if x = 0, we have:
y = 2*0 + 3
y = 3
Then the pointis (0, 3)
if x = 1
y = 2*1 + 3
y = 2 + 3 = 5
Then we have the point (1, 5)
Then we can graph these two points and connect them with a line, then the graph is the one you can see below.
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verify each x value
3. [-/5 Points] (a) X = Verify that each x-value is a solution of the equation. 2 sec(x) -4 = 0 2 DETAILS sec()-4 Submit Answer IT 57 (b) 3 2 sec (5) - X = 11 = 0
(a) X = Verify that each x-value is a solution of the equation. 2 sec(x) -4 = 0
To verify whether x is a solution of the equation 2 sec(x) -4 = 0, we have to substitute x in the equation and check whether the left-hand side of the equation equals the right-hand side of the equation or not.
Let's verify it by substituting x in the given equation 2 sec(x) -4 = 0:2 sec(x) - 4 = 02 sec(x) = 4sec(x) = 2 / 2sec(x) = 1
The value of sec(x) is 1 if x = 0° or x = 360°.
Thus, 0° and 360° are the solutions of the given equation.
(b) 3 2 sec (5) - X = 11 = 0
To verify whether x is a solution of the equation 3 2 sec (5) - X = 11 = 0, we have to substitute x in the equation and check whether the left-hand side of the equation equals the right-hand side of the equation or not.
Let's verify it by substituting x in the given equation 3 2 sec (5) - X = 11 = 0:3 2 sec (5) - x = 11 = 03 sec (5) = x + 11sec (5) = (x + 11) / 3The value of sec(5) can't be found by using the trigonometric ratios.
Therefore, we can't find the solution of the given equation.
Hence, the solution is undefined.
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4. Use an Addition or Subtraction formula to find the exact value of the expression \( \cos \frac{\pi}{12} \cos \frac{5 \pi}{12}+\sin \frac{\pi}{12} \sin \frac{5 \pi}{12} \). Show your work and do not
The expression [tex]\( \cos \frac{\pi}{12} \cos \frac{5 \pi}{12}+\sin \frac{\pi}{12} \sin \frac{5 \pi}{12} \)[/tex]can be simplified using the Addition or Subtraction formula for cosine.the exact value of the given expression is[tex]\( \frac{\sqrt{3}}{2} \).[/tex]
We can use the Addition formula for cosine, which states that[tex]\( \cos(\alpha + \beta) = \cos \alpha \cos \beta - \sin \alpha \sin \beta \).[/tex]
Let's rewrite the given expression in terms of this formula:
[tex]\( \cos \frac{\pi}{12} \cos \frac{5 \pi}{12}+\sin \frac{\pi}{12} \sin \frac{5 \pi}{12} \)[/tex]
Now, let's set [tex]\( \alpha = \frac{\pi}{12} \) and \( \beta = \frac{5 \pi}{12} \):[/tex]
[tex]\( \cos(\frac{\pi}{12} + \frac{5 \pi}{12}) \)[/tex]
Simplifying the angle inside the cosine function:
[tex]\( \cos(\frac{6 \pi}{12}) \)[/tex]
[tex]\( \cos(\frac{\pi}{2}) \)[/tex]
Since the cosine of [tex]\( \frac{\pi}{2} \)[/tex] is 0, the expression simplifies to:
[tex]\( 0 \)[/tex]
Therefore, the exact value of the expression is[tex]\( \frac{\sqrt{3}}{2} \).[/tex]
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Consider the differential equation dy dt 1 - t² Sketch the slope field from -2 ≤ t ≤ 2 and −-2 ≤ y ≤ 2 and plot the solution curve with the initial condition y(0) = 1.
The graph is attached and the value of the function is -0.4 at x = 0.7.
Any equation with a variable difference in it is a difference equation then variables affect how different equations are categorized.
y = Mt (x - 1) + 0
Where M = 1/3 x 1(0-2)²
M = 1/3 x 4
M = 4/3
From equation 1;
y = (4/3)(x - 1)
Function at x = 0.7
f(0.7) = 4/3(0.7 -1 )
= 4/3(-0.3)
Let, u = y - 2
du = dy
-1/u = 1/3( x²/2) + c
-1/(y+2) = x²/6 + c
At point(1 , 0 )
c = 2/6
Therefore,-1/(y-2) = x²/ 6 - 1/3
y = -6/(x² + 2) + 2
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Give a non-zero vector in the null space of A A- -5 5 3 -3-2
Let's define a few terms before solving the problem.
Non-zero vector: In mathematics, a non-zero vector is any vector that has a magnitude or length greater than zero. We can find a non-zero vector in the null space of a matrix with the help of a row operation.
Null space: The null space of a matrix A is the set of all vectors x that can be multiplied by A to produce the zero vector 0.
[tex]Mathematically, we can write it as Null (A) = {x|Ax=0}.Solution: The given matrix is A- = \[\begin{pmatrix}-5 & 5\\ 3 & -3\\ -2 & 0\end{pmatrix}\][/tex]
We have to find the null space of matrix A-.
[tex]Let's write the augmented matrix of A-.For this, we add a column of zeros to the right of matrix A- and write it as follows: \[\begin{pmatrix}-5 & 5 & 0\\ 3 & -3 & 0\\ -2 & 0 & 0\end{pmatrix}\][/tex]
Next, we perform row operations to reduce the matrix to a reduced row echelon form.
In the reduced row echelon form of the matrix, the basic variables are the leading 1s in each row.
The non-basic variables are the free variables that can take any value.
The null space is spanned by the non-basic variables in the matrix.
A row operation involves swapping two rows, multiplying a row by a non-zero constant or adding a multiple of one row to another row. We can represent these operations with the help of elementary matrices.
Let's perform row operations on the augmented matrix to obtain the reduced row echelon form.
[tex]\[\begin{pmatrix}-5 & 5 & 0\\ 3 & -3 & 0\\ -2 & 0 & 0\end{pmatrix}\xrightarrow[]{R_1+R_3} \begin{pmatrix}-5 & 5 & 0\\ 3 & -3 & 0\\ 0 & 5 & 0\end{pmatrix}\xrightarrow[]{R_1+R_2} \begin{pmatrix}-5 & 5 & 0\\ 0 & 2 & 0\\ 0 & 5 & 0\end{pmatrix}\][/tex]
Now, we can see that the first and second columns of the matrix are the basic variables, while the third column is the non-basic variable. The corresponding free variable is x3 which can take any value.
[tex]We can express the null space of the matrix as Null (A) = {x | Ax = 0}, where x = \[\begin{pmatrix}x_1\\x_2\\x_3\end{pmatrix}\].[/tex]
To find a non-zero vector in the null space of A-, we can set the free variable x3 = 1 and solve for x1 and x2 from the matrix equation Ax = 0.Substituting x3 = 1, we get the following equations: -5x1 + 5x2 = 0 2x2 = 0
Solving for x2, we get x2 = 0. Substituting x2 = 0 in the first equation, we get x1 = 0. Therefore, the non-zero vector in the null space of A- is \[\begin{pmatrix}0\\0\\1\end{pmatrix}\].
[tex]Answer: The non-zero vector in the null space of A- is \[\begin{pmatrix}0\\0\\1\end{pmatrix}\].[/tex]
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The demand for a product is given by the following demand function: D(q)-0.006q+81 where q is units in demand and D(q) is the price per item, in dollars. If 2, 300 units are in demand, what price can be charged for each item? Answer: Price per unit - S Submit Question 27
The price that can be charged for each item is $67.8.
Given demand function is D(q) = -0.006q + 81.
We need to find the price per unit of the item, when 2,300 units are in demand.
We know that the demand function is D(q) = Price of item (in dollars).
Therefore, D(q) = P(q)
Price per unit = P(2300)
We are given, q = 2,300
D(q) = -0.006q + 81
∴ P(q) = P(2300)
= D(q)
P(2300) = D(2300)
= -0.006(2300) + 81
= $67.8
Therefore, the price that can be charged for each item is $67.8.
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Consider the function w(x)=12x 5
−60x 4
−100x 3
+4. Differentiate w and use the derivative to determine each of the following. All intervals on which w is increasing. If there are more than one intervals, separate them by a comma. Use open intervals and exact values. w increases on: All intervals on which w is decreasing. If there are more than one intervals, separate them by a corma. Use open intervals and exact values. we decreases on: The value(s) of x at which w has a relative maximum. If there are more than one solutions, separate them by a comma. Use exact values. wie has relative maximum(s) at ir = The value(s) of x at which w has a relative minimum. If there are moce than one sotutians, segarate them by a comma. Use exact valioes. w has relative minmum(s) at x=
w has relative maximum(s) at x = -1 and x = 5(4)
w has relative minimum(s) at x = 0.
The given function is, [tex]w(x)=12x^5-60x^4-100x^3+4[/tex]
Differentiating the function w(x)
We get, [tex]w'(x) = 60x^4 - 240x^3- 300x^2[/tex]
At any point x, w'(x) represents the slope of the tangent to the curve at point x.
(1) All intervals on which w is increasing
For w to be increasing w'(x) > 0
For w to be decreasing w'(x) < 0
For w to have a relative maximum w'(x) = 0
[tex]w'(x) = 60x^4 - 240x^3- 300x^2[/tex]
=> [tex]60x^2(x^2- 4x - 5)[/tex]
=> [tex]60x^2(x - 5)(x + 1)[/tex]
Therefore, w is increasing on two intervals which are x ∈ (-∞,-1) U (0,5) (2)
All intervals on which w is decreasing
w is decreasing where w'(x) < 0
[tex]w'(x) = 60x^4 - 240x^3 - 300x^2[/tex]
=> [tex]60x^2(x^2- 4x - 5)[/tex]
=> [tex]60x^2(x - 5)(x + 1)[/tex]
Therefore, w is decreasing on two intervals which are x ∈ (-1,0) U (5,∞)(3)
The value(s) of x at which w has a relative maximum
For w to have a relative maximum w'(x) = 0
[tex]w'(x) = 60x^4 - 240x^3 - 300x^2[/tex]
=> [tex]60x^2(x^2- 4x - 5)[/tex]
=> [tex]60x^2(x - 5)(x + 1)[/tex]
x = -1 and x = 5
Therefore, w has relative maximum(s) at x = -1 and x = 5(4)
The value(s) of x at which w has a relative minimum
For w to have a relative minimum w'(x) = 0
[tex]w'(x) = 60x^4 - 240x³^3 - 300x^2[/tex]
=> [tex]60x^2(x^2 - 4x - 5)[/tex]
=> [tex]60x^2 (x - 5)(x + 1) x = 0[/tex]
Therefore, w has relative minimum(s) at x = 0.
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A lighthouse at point (0, 0) is able to illuminate up to 200 m away. If a boat is stranded at the point (100, 75), is it within the distance of the light's beam? Justify your answer. Draw a sketch. Round your final to two decimal places, as needed.
The distance between two points, (x1, y1) and (x2, y2), is given by the formula:
Distance =[tex]√((x2-x1)^2+(y2-y1)^2)[/tex]
Therefore, the distance between the lighthouse at point (0,0) and the boat at point (100,75) is:
Distance =[tex]√((100-0)^2+(75-0)^2)≈125 m[/tex]
Since the distance from the boat to the lighthouse is less than the light's beam of 200 m, the boat is within the distance of the light's beam, and thus the lighthouse can illuminate the boat.
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MacLaurin Series for cos(x)
Compute the Maclaurin series for \( \cos (x) \). Show work
Therefore, the Maclaurin series for cos(x) is: [tex]cos(x) = 1 - (x^2/2!) + (x^4/4!) - ...[/tex]
To derive the Maclaurin series for the cosine function, we can start by finding the derivatives of the function evaluated at x = 0.
Let's begin by finding the derivatives of cos(x):
f(x) = cos(x)
f(x) = -sin(x)
f(x) = -cos(x)
f(x) = sin(x)
f(x) = cos(x)
...
Now, let's evaluate these derivatives at x = 0:
cos(0) = 1
-sin(0) = 0
-cos(0) = -1
sin(0) = 0
cos(0) = 1
...
We can observe that the derivatives of cos(x) alternate between 1, 0, -1, 0, 1, 0, and so on.
The Maclaurin series for cos(x) is given by:
[tex]cos(x) = f(0) + f'(0)x + (f''(0)/2!)x^2 + (f'''(0)/3!)x^3 + (f''''(0)/4!)x^4 + ...[/tex]
Substituting the values we obtained earlier:
[tex]cos(x) = 1 + 0x - (1/2!)x^2 + 0x^3 + (1/4!)x^4 - ...[/tex]
Simplifying the expression, we get:
[tex]cos(x) = 1 - (x^2/2!) + (x^4/4!) - ...[/tex]
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1. In a recent month, the percentage of negative results at a Covid-19 test site was approximately 70%. Suppose that there are five customers took a test. Find the probability that (2 points each)
1) none of them got positive result
2) at least two of them got positive results
1) The probability that none of them got a positive result is 0.1681.
2) The probability that at least two of them got positive results is 0.47175.
To solve the problem, we need to use the binomial distribution formula:
P(X=k) = (n choose k) * p^k * (1-p)^(n-k)
where:
- n is the number of trials
- k is the number of successes
- p is the probability of success
For the first part of the question, we want to find the probability that none of the five customers got a positive result. Since the percentage of negative results is 70%, the probability of a positive result is 30% or 0.3. Therefore, we have:
P(X=0) = (5 choose 0) * 0.3^0 * 0.7^5 = 0.1681
For the second part of the question, we want to find the probability that at least two of them got positive results. We can approach this problem by finding the probability that none or only one customer got a positive result, and then subtracting that from 1 to get the probability that at least two got positive results. So we have:
P(X=0) = (5 choose 0) * 0.3^0 * 0.7^5 = 0.1681
P(X=1) = (5 choose 1) * 0.3^1 * 0.7^4 = 0.36015
P(X≤1) = P(X=0) + P(X=1) = 0.52825
P(X≥2) = 1 - P(X≤1) = 1 - 0.52825 = 0.47175
So the probability positive results is 0.47175.
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Calculate The Radius Of Convergence And Interval Of Convergence For The Power Series ∑N=1[infinity]N2+1(X−3)N. Show All Of
The power series ∑N=1[infinity]N2+1(X−3)N has a radius of convergence of 1 and an interval of convergence of (2, 4).
To determine the radius of convergence and interval of convergence for the power series, we can use the ratio test.
Applying the ratio test, we calculate the limit of the absolute value of the ratio of consecutive terms: lim[N→∞] |(N+1)²+1(X-3)^(N+1) / N²+1(X-3)^N|
Taking the absolute value and simplifying the expression:
lim[N→∞] |(N+1)²+1(X-3) / N²+1|
This limit can be further simplified as: lim[N→∞] |(1 + 1/N)²+1(X-3)|
Since the limit does not depend on N or the terms of the series, the series converges for all values of X within a certain interval.
To find the radius of convergence, we set the limit less than 1:
|(1 + 1/N)²+1(X-3)| < 1
Simplifying the inequality, we get: |(X-3)| < 1
This shows that the series converges when the absolute value of (X-3) is less than 1, or when X is within the interval (2, 4).
Therefore, the power series has a radius of convergence of 1 and an interval of convergence of (2, 4).
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We want to use the Alternating Series Test to determine if the series: ∑ k=1
[infinity]
(−1) k+1
k 3
+7
k 2
converges or diverges. We can conclude that: The Alternating Series Test does not apply because the absolute value of the terms do not approach 0 , and the series diverges for the same reason. The Alternating Series Test does not apply because the absolute value of the terms are not decreasing, but the series does converge. The series converges by the Alternating Series Test. The series diverges by the Alternating Series Test. The Alternating Series Test does not apply because the terms of the series do not alternate.
The correct option is:The series diverges by the Alternating Series Test.
To determine whether the given series ∑(−1)k+1 (k^3+7/k^2) converges or diverges, we will use the alternating series test.
Alternating Series Test: The alternating series test, also known as Leibniz's test, is a test that determines whether a series of alternating terms converges.
This test applies only to alternating series whose terms decrease in absolute value (that is, |a[n+1]| ≤ |a[n]| for all n) and that converge to zero.
An alternating series of the form∑(−1)k+1 a[k], where a[k]>0 for all k and a[k+1]≤a[k] for all k, is said to be convergent.
The terms of the given series are not decreasing and the series does not converge to 0, so we cannot apply the alternating series test.
We can infer from this that the series diverges, which is option D.
Therefore, the correct option is:The series diverges by the Alternating Series Test.
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Solve the following exponential equation. Express irrational solutions in exact form and as a decimal founded to three decimal places: 5(95x)=2 What is the exact answer? Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The solution set is . (Simplify your answer. Type an exact answer.) B. There is no solution. What is the answer rounded to three decimal places? Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The solution set is (Simplify your answer. Type an integer or decimal rounded to three decimal places as needed.) B. There is no solution.
A. The solution set is \(\left\{ \frac{1}{5} \log_9 \left(\frac{2}{5}\right) \right\}\) (exact form). A. The solution set is \(-0.039\) (rounded to three decimal places).
To solve the exponential equation \(5 \cdot (9^5x) = 2\), we can start by isolating the exponential term:
\[9^5x = \frac{2}{5}\]
To eliminate the exponent, we can take the logarithm (base 9) of both sides:
\[\log_9 (9^5x) = \log_9 \left(\frac{2}{5}\right)\]
Using the property of logarithms that \(\log_a (a^b) = b\), we have:
\[5x = \log_9 \left(\frac{2}{5}\right)\]
Next, we divide both sides of the equation by 5:
\[x = \frac{1}{5} \log_9 \left(\frac{2}{5}\right)\]
To evaluate \(\log_9 \left(\frac{2}{5}\right)\) in decimal form, we can use the change of base formula:
\[\log_9 \left(\frac{2}{5}\right) = \frac{\log \left(\frac{2}{5}\right)}{\log 9}\]
Using a calculator, we find:
\[\log_9 \left(\frac{2}{5}\right) \approx -0.193\]
Therefore, the exact solution to the equation \(5 \cdot (9^5x) = 2\) is:
\[x = \frac{1}{5} \log_9 \left(\frac{2}{5}\right) \approx -0.0386\]
Rounded to three decimal places, the solution is approximately \(x = -0.039\).
The correct answer is:
A. The solution set is \(\left\{ \frac{1}{5} \log_9 \left(\frac{2}{5}\right) \right\}\) (exact form).
A. The solution set is \(-0.039\) (rounded to three decimal places).
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Find The Absolute Maximum And Minimum Values Of The Following Function On The Given Region R. F(X,Y)=7x2+7y2−14x+23;R=
To find the absolute maximum and minimum values of the function F(x, y) = 7x^2 + 7y^2 - 14x + 23 on the given region R, we need to analyze the critical points and the boundary of R.
First, let's find the critical points by taking the partial derivatives of F(x, y) with respect to x and y and setting them equal to zero:
∂F/∂x = 14x - 14 = 0
∂F/∂y = 14y = 0
From the first equation, we find x = 1. Substituting this value into the second equation, we get y = 0. Therefore, the critical point is (1, 0).
Next, let's examine the boundary of R. Unfortunately, you haven't provided the region R, so we cannot analyze its boundary or determine the absolute maximum and minimum values of the function without knowing the constraints on x and y.
If you provide the specific region R, including its constraints or boundaries, I will be able to help you further in finding the absolute maximum and minimum values of the function F(x, y) within that region.
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The function provided is a quadratic equation in terms of x and y. It is impossible to definitively provide the absolute maximum or minimum of the function without knowing the region R. However, we can find the x-coordinate of the vertex as -b/2a which is 1 for the given function.
Explanation:The function provided is in terms of x and y, and is a quadratic equation. These types of equations often have minimum or maximum values, depending on their facing direction (upwards or downwards). Unfortunately, without the given region R it is impossible to definitively provide the absolute maximum and minimums for the function.
However, the maximum or minimum of a quadratic function is achieved at its vertex. The x-coordinate of the vertex of a general quadratic function, f(x) = ax^2+bx+c, is given by -b/2a. Hence, the x-coordinate of the vertex of the given function is -(-14)/(2*7) = 1.
Substituting x = 1 into the function to get the y-coordinate of the vertex gives f(1,y) = 7*1^2+7y^2+14+23 = 23+y^2. Since this is still a quadratic in y, the y-coordinate of the function's minimum or maximum is also not determinable without more information.
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Please help!
Algebra 3
Find the Domain and Range.
The domain and the range of the function are (-∝, ∝) and (-∝, 2), respectively
Calculating the domain and range of the graph?From the question, we have the following parameters that can be used in our computation:
The graph
The above graph is an absolute function
The rule of this function is that
The domain is the set of all real values
In this case, the domain is (-∝, ∝)
For the range, we have
Range = (-∝, 2)
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Differentiate. \[ f(x)=\ln \left[\frac{(5 x+7)(x+9)^{6}}{(1-6 x)^{2}}\right] \] \[ \frac{d}{d x}\left[\ln \left[\frac{(5 x+7)(x+9)^{6}}{(1-6 x)^{2}}\right]\right]= \]
Differentiation is a process of finding the derivative of a function. To differentiate, we apply the differentiation rules such as power rule, product rule, quotient rule and chain rule.
We are to find the derivative of the function f(x) given as We have to differentiate it with respect to x, thus we write it as.
Now, we apply the chain rule of differentiation, i.e., if the function is of the form we apply the differentiation rules such as power rule, product rule, quotient rule and chain rule.
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Suppose we had the following summary statistics from two different, independent, approximately normally distributed populations, both with variances equal to σ : 1. Population 1: xˉ 1 =128.8,s 1=15.975,n 1 =5 2. Population 2: xˉ2 =165, s 2 =21.863,n 2 =4 We want to find a 97% confidence interval for μ 2 −μ 1. To do this, answer the below questions. a. Can we assume equal variances or not? Yes, we can assume equal variances. No, we cannot assume equal variances. b. The pooled standard deviation is: s p = Round to 3 decimal places. c. The standard error is: SE= Hint Round to 3 decimal places. d. What is the degrees of freedom associated with this problem? (Round down to the nearest whole number.) The critical value from the distribution for a confidence interval of 97% is: t = Use Technology. Round to 3 decimal places. c. The standard error is: SE= Hint Round to 3 decimal places. d. What is the degrees of freedom associated with this problem? (Round down to the nearest whole number.) The critical value from the distribution for a confidence interval of 97% is:
a) We cannot assume equal variances. b) The pooled standard deviation is approximately 18.596. c) The standard error is approximately 8.364. d) The degrees of freedom associated with this problem is 7.
a. We cannot assume equal variances because the sample sizes are unequal (n1 = 5, n2 = 4) and the sample variances are also different.
b. The pooled standard deviation, sp, is calculated using the formula:
sp = \sqrt{(((n1 - 1) * s1^2 + (n2 - 1) * s2^2) / (n1 + n2 - 2))}
= \sqrt{(((4 * (15.975)^2) + (3 * (21.863)^2)) / (5 + 4 - 2))}
≈ 18.596 (rounded to 3 decimal places)
c. The standard error, SE, is calculated using the formula:
SE = sp * sqrt(1/n1 + 1/n2)
= 18.596 * sqrt(1/5 + 1/4)
≈ 8.364 (rounded to 3 decimal places)
d. The degrees of freedom associated with this problem is calculated using the formula:
df = n1 + n2 - 2
= 5 + 4 - 2
= 7
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It is reported that 10% of people are left-handed. A random sample of 15 people was drawn across the country to investigate this. a) Identify the "trial" here. Are trials independent? Explain your answer in the context of the question. b) Assume this is a proper binomial experiment. Define the binomial random variable in this question. How many possible values does it have? c) Find the mean of the binomial random variable and interpret this value in the context of the question. d) What is the probability that at least 4 but less than 8 are left-handed in this sample?
A random sample of 15 people was drawn to investigate the claim that 10% of people are left-handed. The probability that at least 4 but less than 8 people in the sample are left-handed is calculated using a binomial probability calculator or table.
It is reported that 10% of people are left-handed. A random sample of 15 people was drawn across the country to investigate this. Therefore,
a) The "trial" in this context refers to each person in the random sample being classified as left-handed or not. The trials are assumed to be independent because it is reasonable to assume that the left-handedness of one person does not influence the left-handedness of another person in the sample.
b) The binomial random variable in this question is the number of left-handed people in the random sample of 15. It can take on values from 0 to 15, representing the possible counts of left-handed individuals in the sample.
c) The mean of a binomial random variable is given by the formula μ = np, where n is the sample size and p is the probability of success (being left-handed in this case). Here, n = 15 and p = 0.10. Substituting the values, we get μ = 15 * 0.10 = 1.5. The mean of the binomial random variable is 1.5, which represents the expected number of left-handed individuals in the sample of 15 people.
d) To find the probability that at least 4 but less than 8 people are left-handed in the sample, we need to calculate the cumulative probability from 4 to 7. This can be done by summing the individual probabilities for these values. Using a binomial probability calculator or a binomial probability distribution table, we can find the probabilities for each value and sum them up. The resulting probability will give us the desired value.
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According to the investment management firm, a person with a moderate investment strategy and n years to retirement should have accumulated savings of an percent of his or her annual salary. The geometric sequence defined by a = 1271(0.918) gives the appropriate percent for each year n. (a) Find a, and r. Round a, to the nearest whole number. (b) Find and interpret the terms a₁0 and a20. Round to the nearest whole number. (a) a₁~ (Round to the nearest whole number as needed.)
(a) Therefore, `r = 0.918`.(b) investment strategy and 20 years to retirement should have accumulated savings of approximately 392.82% of his or her annual salary.
(a) To find a and r from the given geometric sequence, use the formula for the nth term in a geometric sequence, which is given by `a_n = a_1 * r^(n-1)`.
The given sequence is a geometric sequence defined by `a = 1271(0.918)`.Here, a is the first term, so `a = a_1`.r is the common ratio between the terms of the sequence.
Therefore, `r = 0.918`.
Using the given formula `a_n = a_1 * r^(n-1)`, we can find the value of a1:a₁ = 1271(0.918) = 1166.758.So, `a` (rounded to the nearest whole number) is 1167. r is given as 0.918.
(b) We need to find the values of `a₁0` and `a20`.Using the formula for the nth term in a geometric sequence `a_n = a_1 * r^(n-1)`, we can find `a₁0` as follows:a₁0 = a_1 * r^(10-1)a₁0 = 1166.758 * 0.918^9a₁0 ≈ 679.02
This means that the person with a moderate investment strategy and 10 years to retirement should have accumulated savings of approximately 679.02% of his or her annual salary.
To find `a20`, use the same formula:a20 = a_1 * r^(20-1)a20 = 1166.758 * 0.918^19a20 ≈ 392.82
This means that the person with a moderate investment strategy and 20 years to retirement should have accumulated savings of approximately 392.82% of his or her annual salary.
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Could you please find the domain of f(x,y) = Sin (Sqrt(xy))/
x-y
In other words, the domain consists of all pairs (x, y) except when x = y or when one of x and y is positive while the other is negative.
To find the domain of the function f(x, y) = sin(sqrt(xy))/(x - y), we need to consider the restrictions imposed by the function itself.
The denominator (x - y) cannot be zero, as division by zero is undefined. Therefore, we need to exclude the values that make the denominator zero. This implies x ≠ y.
The argument of the square root (xy) must be non-negative for the function to be defined. Thus, we need xy ≥ 0, which means either both x and y are non-negative or both x and y are non-positive.
Combining both conditions, the domain of f(x, y) is given by:
x ≠ y and (x ≥ 0, y ≥ 0) or (x ≤ 0, y ≤ 0).
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An object moves according to a law of motion, where, its position is described by the following function, s=f(t)=t 4
−4t+1. The time t is measured in seconds and s in meter. a. Sketch the velocity graph and determine when is the object moving in the positive direction. [3 marks] b. Draw a diagram of the motion of the object and determine the total distance traveled during the first 6 seconds.
a. The velocity graph is an upward curve that crosses the x-axis at t ≈ -0.872. The object is moving in the positive direction when v(t) > 0.
b. The motion diagram shows the curve of the position function f(t) = t⁴- 4t + 1. To find the total distance traveled during the first 6 seconds, we need to calculate the area under the velocity graph by integrating |v(t)| from 0 to t1 and from t1 to 6, where t1 is the first point where v(t) = 0.
To sketch the velocity graph and determine when the object is moving in the positive direction, we need to find the derivative of the position function with respect to time.
a. Velocity graph:The velocity function v(t) is the derivative of the position function f(t). Let's find the derivative:
f(t) = t⁴ - 4t + 1
Taking the derivative of f(t) with respect to t:
f'(t) = 4t³ - 4
The velocity function v(t) is given by f'(t), which is:
v(t) = 4t³ - 4
To sketch the velocity graph, we plot v(t) on the y-axis and t on the x-axis. The graph will help us determine when the object is moving in the positive direction.
b. Motion diagram and total distance traveled:To draw a diagram of the motion, we need to plot the position of the object on the y-axis and time on the x-axis. The total distance traveled during the first 6 seconds can be calculated by finding the area under the velocity curve.
Let's proceed with sketching the velocity graph and motion diagram:
a. Velocity graph:
We plot v(t) = 4t³ - 4 on the y-axis and t on the x-axis:
```
|
| + +
| . .
v(t) | . .
| . .
| .
|_____________________________
t
```
The graph shows an upward curve that starts below the x-axis, crosses it at t ≈ -0.872, and continues above the x-axis. The object is moving in the positive direction when v(t) > 0.
b. Motion diagram:
We plot the position function f(t) = t⁴ - 4t + 1 on the y-axis and t on the x-axis:
```
|
| + +
| . .
s(t) | . .
| . .
| .
|_____________________________
t
```
The motion diagram shows the curve of the function f(t) = t⁴ - 4t + 1.
To determine the total distance traveled during the first 6 seconds, we need to calculate the area under the velocity graph for t between 0 and 6.
Using definite integration:
Total distance = ∫(0 to 6) |v(t)| dt
Total distance = ∫(0 to 6) |4t³ - 4| dt
This integration can be split into two parts, from 0 to the first point where v(t) = 0, and from there to 6.
For the first part, we integrate |v(t)| from 0 to t1, where v(t1) = 0:
Total distance = ∫(0 to t1) (4t³ - 4) dt
For the second part, we integrate |v(t)| from t1 to 6:
Total distance = ∫(t1 to 6) (4t³ - 4) dt
To solve these integrals and find the total distance traveled during the first 6 seconds, we need to determine the value of t1, where v(t1) = 0. We can find this value by setting 4t³ - 4 = 0 and solving for t.
Once we have the value of t1, we can calculate the total distance by evaluating the integrals.
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Check all rules that must be used to find the derivative of the following function as it is currently written. g(x)=5x3ex Product Rule Logarithmic Rule Sum/Difference Rule Constant Rule Power Rule Exponential Rule Constant Multiple Rule (Constant Times a Function) General Power Rule Quotient Rule Suppose that there is a function f(x) for which the following information is true: The domain of f(x) is all real numbers f′(x)=0 at x=1 and x=5 f′(x) is never undefined f′(x) is positive for all x less than 1 and for all x greater than 5 f′(x) is negative for all x greater than 1 but less than 5 Which of the following statements are true of f(x) ? Check ALL THAT APPLY. f has an absolute maximum point. The graph of f has a local maximum at the point where x=1. The graph of f has a local minimum at the point where x=1. f has no critical values. The graph of f has a local maximum at the point where x=5. f has an absolute minimum point. f has exactly two critical values. f has exactly one critical value. The graph of f has a local minimum at the point where x=5. On your paper label this problem as "OPTIMIZATION". A sandwich shop knows that it will sell 400 sandwiches daily when charging $3/ sandwich. For every $0.50 increase in price, daily sales drop by 10 sandwiches. What price should be set to maximize daily revenue? (You can leave the answer space below blank.)
The derivative of g(x) = 5x³eˣ is 15x²eˣ, and the conclusions for f(x) include having an absolute maximum, local maximum at x=1, local minimum at x=5, two critical values, and one critical value.
For the first question:
To find the derivative of g(x) = 5x³eˣ, we apply the rules step by step:
Apply the Constant Rule: The derivative of 5x³ is 15x².
Apply the Power Rule: The derivative of eˣ is eˣ.
Apply the Constant Multiple Rule: Multiply the derivative of 5x³ by eˣ, giving us 15x²eˣ.
Therefore, the derivative of g(x) is 15x²eˣ.
For the second question:
Based on the given information about f(x), we can conclude the following:
f has an absolute maximum point.
The graph of f has a local maximum at x = 1.
The graph of f has a local minimum at x = 5.
f has exactly two critical values.
f has exactly one critical value.
These conclusions are derived from the information about f′(x) being positive for x < 1 and x > 5, and negative for 1 < x < 5, as well as f′(x) being zero at x = 1 and x = 5.
For the third question:
To determine the price that should be set to maximize daily revenue, we need to set up an equation for revenue and optimize it. We know that revenue is equal to the price per sandwich multiplied by the number of sandwiches sold. By observing the given information, we can deduce that for every $0.50 increase in price, the number of sandwiches sold decreases by 10. Using this information, we can set up the revenue equation and then differentiate it with respect to price to find the maximum value.
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Find the surface area of
the rectangular prism.
First, find the area of top
and bottom rectangles.
Area of the top and
bottom rectangles: [?] cm²
Area of the side
2
rectangles: []cm
Area of the
front and back:
Total Area:
2
cm²
2
cm
8 cm
10 cm
12 cm
The total surface area of the rectangular prism is 592 cm².
To find the surface area of a rectangular prism, we need to calculate the areas of its individual faces and then sum them up. Let's calculate the requested areas:
1. Area of the top and bottom rectangles:
The top and bottom faces of a rectangular prism have the same dimensions, so we can calculate the area of one face and double it.
Area of a rectangle = Length × Breadth
Length = 12 cm
Breadth = 8 cm
Area of one face = Length × Breadth = 12 cm × 8 cm = 96 cm²
Area of top and bottom rectangles = 2 × Area of one face = 2 × 96 cm² = 192 cm²
Therefore, the area of the top and bottom rectangles is 192 cm².
2. Area of the side rectangles:
The side faces are also rectangles, and they have the dimensions of the length and height.
Area of one side face = Length × Height = 12 cm × 10 cm = 120 cm²
Since there are two side faces, we multiply the area of one side face by 2.
Area of side rectangles = 2 × Area of one side face = 2 × 120 cm² = 240 cm²
The area of the side rectangles is 240 cm².
3. Area of the front and back:
The front and back faces are also rectangles, and they have the dimensions of the breadth and height.
Area of one front/back face = Breadth × Height = 8 cm × 10 cm = 80 cm²
Again, since there are two front/back faces, we multiply the area of one face by 2.
Area of front and back = 2 × Area of one front/back face = 2 × 80 cm² = 160 cm²
The area of the front and back is 160 cm².
4. Total surface area:
To find the total surface area,we need to sum up all the individual areas.
Total surface area = Area of top and bottom rectangles + Area of side rectangles + Area of front and back
Total surface area = 192 cm² + 240 cm² + 160 cm² = 592 cm²
Therefore, the total surface area of the rectangular prism is 592 cm².
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The Probable question may be:
Find the surface area of the rectangular prism.
First, find the area of top and bottom rectangles.
Length = 12cm,Breadth = 8cm,Height=10cm.
Find
1. Area of the top and bottom rectangles: cm²
2. Area of the side rectangles in cm².
3. Area of the front and back in cm².
4. Total Area in cm.
Can you help me calculate x and y. I’ll mark u brainliest
Answer:
x and y =70
Step-by-step explanation:
4. (cont) (c) \( \lim _{x \rightarrow-1} \frac{\sqrt{-3 x}-\sqrt{3}}{x+1} \)
According to the question on simplify we get: [tex]\[ \lim_{{x \to -1}} \frac{-6\sqrt{3}}{0} \][/tex]
To find the limit of the function [tex]\( \frac{\sqrt{-3x}-\sqrt{3}}{x+1} \) as \( x \)[/tex] approaches -1, we can directly substitute -1 into the expression and simplify:
[tex]\[ \lim_{{x \to -1}} \frac{\sqrt{-3x}-\sqrt{3}}{x+1} = \frac{\sqrt{-3(-1)}-\sqrt{3}}{(-1)+1} = \frac{\sqrt{3}-\sqrt{3}}{0} \][/tex]
Since the denominator is 0, we have an indeterminate form. We need to apply further algebraic manipulation to evaluate the limit.
To eliminate the square roots, we can multiply both the numerator and denominator by the conjugate of the numerator, which is [tex]\( \sqrt{-3x}+\sqrt{3} \):[/tex]
[tex]\[ \lim_{{x \to -1}} \frac{\sqrt{-3x}-\sqrt{3}}{x+1} \cdot \frac{\sqrt{-3x}+\sqrt{3}}{\sqrt{-3x}+\sqrt{3}} \][/tex]
Simplifying the expression, we have:
[tex]\[ \lim_{{x \to -1}} \frac{(-3x-3)-(\sqrt{3x}-\sqrt{3})(\sqrt{3x}+\sqrt{3})}{(x+1)(\sqrt{-3x}+\sqrt{3})} \][/tex]
Further simplifying the numerator, we get:
[tex]\[ \lim_{{x \to -1}} \frac{-3x-3-(\sqrt{3x})^2-\sqrt{3}\sqrt{3}-\sqrt{3x}\sqrt{3}-\sqrt{3}\sqrt{3}}{(x+1)(\sqrt{-3x}+\sqrt{3})} \][/tex]
Simplifying the numerator, we have:
[tex]\[ \lim_{{x \to -1}} \frac{-3x-3-3x-3\sqrt{3}-3\sqrt{3}}{(x+1)(\sqrt{-3x}+\sqrt{3})} \][/tex]
Combining like terms, we get:
[tex]\[ \lim_{{x \to -1}} \frac{-6x-6-6\sqrt{3}}{(x+1)(\sqrt{-3x}+\sqrt{3})} \][/tex]
Now, substituting [tex]\( x = -1 \)[/tex] into the expression, we have:
[tex]\[ \lim_{{x \to -1}} \frac{-6(-1)-6-6\sqrt{3}}{(-1+1)(\sqrt{-3(-1)}+\sqrt{3})} = \frac{6-6-6\sqrt{3}}{(0)(\sqrt{3}+\sqrt{3})} \][/tex]
Simplifying further, we get:
[tex]\[ \lim_{{x \to -1}} \frac{-6\sqrt{3}}{0} \][/tex]
Since the denominator is 0 and the numerator is not zero, we have an indeterminate form. Therefore, we need to use additional techniques, such as L'Hôpital's rule or algebraic manipulation, to evaluate the limit.
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Janice was hired for a salary of 40,000 per year. At the end of the first year, she gets a raise of 8%. Unfortunately at the end of the second year the boss asks everyone to take a 5% pay cut from their second year salary what will Janice’s salary be for her third year on the job.
A. 38,000
B. 41,040
C. 41,200
D. 43,195
Answer:
B. 41,040
Step-by-step explanation:
Janice has a rollercoaster ride of a salary. She starts with 40,000 bucks a year, which is not bad. But then she gets a sweet 8% raise after the first year, which bumps her up to 43,200. That's a nice chunk of change. But then disaster strikes. She has to take a 5% pay cut after the second year, which brings her down to 41,040. Ouch. That hurts. She hopes for a better third year, but nothing changes. She's stuck with 41,040 for the whole year. Poor Janice.
How do we know all this? Well, we use some math magic called percentage increase and decrease. It's a simple formula that tells us how much something changes when it goes up or down by a certain percentage. Here it is:
percentage increase/decrease = (new value - old value) / old value × 100%
We can use this formula to find Janice's new salary after each year. For example, after the first year, her new salary is 8% more than her old salary of 40,000. So we plug in the numbers and get:
percentage increase = (43,200 - 40,000) / 40,000 × 100%
percentage increase = 3,200 / 40,000 × 100%
percentage increase = 0.08 × 100%
percentage increase = 8%
That checks out. We can do the same thing for the second year, but this time we have to use percentage decrease because her salary goes down by 5%. So we get:
percentage decrease = (41,040 - 43,200) / 43,200 × 100%
percentage decrease = -2,160 / 43,200 × 100%
percentage decrease = -0.05 × 100%
percentage decrease = -5%
That also checks out. And for the third year, there is no change in her salary, so the percentage increase/decrease is zero.
So now we know Janice's salary for each year: 40,000 for the first year, 43,200 for the second year, and 41,040 for the third year. The question asks us what her salary is for the third year, so the answer is B.