Help the question says "Solve -2b – 12 = 22" and the answers are

Use the given transformation x=4u, y=3v to evaluate the integral. ∬r4x2 da, where r is the region bounded by the ellipse x216 y2

exis [7]

The Jacobian for this transformation is

$J = \begin{bmatrix} x_u & x_v \\ y_u & y_v \end{bmatrix} = \begin{bmatrix} 4 & 0 \\ 0 & 3 \end{bmatrix}$

with determinant $|J| = 12$ , hence the area element becomes

$dA = dx\,dy = 12 \, du\,dv$

Then the integral becomes

$\displaystyle \iint_{R'} 4x^2 \, dA = 768 \iint_R u^2 \, du \, dv$

where $R'$ is the unit circle,

$\dfrac{x^2}{16} + \dfrac{y^2}9 = \dfrac{(4u^2)}{16} + \dfrac{(3v)^2}9 = u^2 + v^2 = 1$

so that

$\displaystyle 768 \iint_R u^2 \, du \, dv = 768 \int_{-1}^1 \int_{-\sqrt{1-v^2}}^{\sqrt{1-v^2}} u^2 \, du \, dv$

Now you could evaluate the integral as-is, but it's really much easier to do if we convert to polar coordinates.

$\begin{cases} u = r\cos(\theta) \\ v = r\sin(\theta) \\ u^2+v^2 = r^2\\ du\,dv = r\,dr\,d\theta\end{cases}$

Then

$\displaystyle 768 \int_{-1}^1 \int_{-\sqrt{1-v^2}}^{\sqrt{1-v^2}} u^2\,du\,dv = 768 \int_0^{2\pi} \int_0^1 (r\cos(\theta))^2 r\,dr\,d\theta \\\\ ~~~~~~~~~~~~ = 768 \left(\int_0^{2\pi} \cos^2(\theta)\,d\theta\right) \left(\int_0^1 r^3\,dr\right) = \boxed{192\pi}$

3 0

1 year ago

Which piecewise function is shown in the graph?

mash [69]

Based on the characteristics of linear and piecewise functions, the piecewise function $f(x) = \left \{ {{-0.5\cdot x +1, \,x < 0} \atop {2\cdot x - 2, \,x \ge 0}} \right.$ is shown in the graph attached herein. (Correct choice: A)

<h3>How to determine a piecewise function</h3>

In this question we have a graph formed by two different linear functions. Linear functions are polynomials with grade 1 and which are described by the following formula:

y = m · x + b (1)

Where:

x - Independent variable.
y - Dependent variable.
m - Slope
b - Intercept

By direct observation and by applying (1) we have the following piecewise function:

$f(x) = \left \{ {{-0.5\cdot x +1, \,x < 0} \atop {2\cdot x - 2, \,x \ge 0}} \right.$

Based on the characteristics of linear and piecewise functions, the piecewise function $f(x) = \left \{ {{-0.5\cdot x +1, \,x < 0} \atop {2\cdot x - 2, \,x \ge 0}} \right.$ is shown in the graph attached herein. (Correct choice: A)

To learn more on piecewise functions: brainly.com/question/12561612

#SPJ1

3 0

1 year ago

In which quadrant is (4,-5) located

Vinvika [58]

4 in (4,-5) implies positive x-axis.
-5 in (4,-5) implies negative y-axis.

Since x is positive and y is negative in fourth quadrant, so the answer is

QUADRANT IV (or 4th quadrant.

3 0

2 years ago

Read 2 more answers

Let's say we have a sample of 57 participants in a study, what would the degrees of

fiasKO [112]

Answer:

56

Step-by-step explanation:

degree of freedom is n - 1, n being the sample size

One sample of 57 participants in a study (given)

For this study, n = 57

Using the degree of freedom formula, 57 - 1 = 56

Hope it helps, Let me know if yoy have any more questions/concerns !

Have a nice rest of your day :)

5 0

1 year ago

Item 11 The height of the house is 26 feet. What is the height x of each story?

Black_prince [1.1K]

26/ by the number of stories

4 0

3 years ago