/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 40 Let \(R\) be the region bounded ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Let \(R\) be the region bounded by the following curves. Use the disk or washer method to find the volume of the solid generated when \(R\) is revolved about the \(y\) -axis. $$y=\sin ^{-1} x, x=0, y=\pi / 4$$

Short Answer

Expert verified
The volume of the solid generated is \(V=\frac{\pi^2}{8}-\frac{\pi}{4}\).

Step by step solution

01

Analyze the given curves

We will first analyze the given equations: - \(y=\sin^{-1}x\): This equation represents the inverse sine function. - \(x=0\): This is a vertical line along the y-axis. - \(y=\pi/4\): This is a horizontal line cutting the inverse sine curve when \(y=\pi/4\). The region R is formed by these equations and when revolved around the y-axis, it forms a solid.
02

Choose the disk or washer method

Since the region R is revolved around the y-axis, we can use the disk method by considering horizontal slices of the region.
03

Set up the equation for a typical disk

The area of a typical disk is \(A(y)=\pi r^2\), where r is the radius. In this case, the radius will be the x-coordinate of the inverse sine function curve, which is \(r=x\). Since \(y=\sin^{-1}x\), we have \(x=\sin y\). Thus, the area of a disk becomes \(A(y)=\pi(\sin y)^2\).
04

Set up the integral to find the volume

To find the volume, we will integrate the area over the given interval for y. The bounds for the integral are from \(y = 0\) to \(y = \pi/4\). Therefore, the integral for the volume will be: $$V = \int_{0}^{\pi/4} \pi(\sin y)^2 dy$$
05

Evaluate the integral

To evaluate the integral, we can use the double-angle formula: \(\sin^2{y} = \frac{1}{2}(1-\cos{2y})\). So, our integral becomes: $$V = \int_{0}^{\pi/4} \pi \cdot \frac{1}{2}(1-\cos{2y}) dy$$ Now, we can integrate: $$V=\pi \cdot \frac{1}{2} \left[ y - \frac{1}{2}\sin{2y} \right]_{0}^{\pi/4}$$ Evaluating at the bounds: $$V = \pi \cdot \frac{1}{2} \left(\left[ \frac{\pi}{4} - \frac{1}{2}\sin{\left(\frac{\pi}{2}\right)}\right] - \left[ 0 - \frac{1}{2}\sin{0} \right]\right)$$
06

Simplify the expression

Simplify the expression, remembering that \(\sin(\pi/2) = 1\) and \(\sin(0)=0\): $$V = \pi \cdot \frac{1}{2} \left( \frac{\pi}{4} - \frac{1}{2} \right)$$
07

Calculate the volume

Calculate the final volume: $$V=\frac{1}{2}\pi\left(\frac{\pi}{4}-\frac{1}{2}\right)=\frac{\pi^2}{8}-\frac{\pi}{4}$$ Thus, the volume of the solid generated when the region R is revolved around the y-axis is \(V=\frac{\pi^2}{8}-\frac{\pi}{4}\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Evaluate the following integrals. $$\int_{0}^{5} 5^{5 x} d x$$

A swimming pool is \(20 \mathrm{m}\) long and \(10 \mathrm{m}\) wide, with a bottom that slopes uniformly from a depth of \(1 \mathrm{m}\) at one end to a depth of \(2 \mathrm{m}\) at the other end (see figure). Assuming the pool is full, how much work is required to pump the water to a level \(0.2 \mathrm{m}\) above the top of the pool?

Use l'Hôpital's Rule to evaluate the following limits. \(\lim _{x \rightarrow 0} \frac{\tanh ^{-1} x}{\tan (\pi x / 2)}\)

Evaluate each expression without using a calculator, or state that the value does not exist. Simplify answers to the extent possible. a. \(\mathrm{cosh 0}\) b. \(\mathrm{tanh 0}\) c. \(\mathrm{csch 0}\) d. \(\mathrm{sech}(sinh 0)\) e. \(\operatorname{coth}(\ln 5) \quad\) f. \(\sinh (2 \ln 3)\) g. \(\cosh ^{2} 1 \quad\) h. \(\operatorname{sech}^{-1}(\ln 3)\) i. \(\cosh ^{-1}(17 / 8)\) j. \(\sinh ^{-1}\left(\frac{e^{2}-1}{2 e}\right)\)

Refer to Exercises 95 and 96. a. Compute a jumper's terminal velocity, which is defined as \(\lim _{t \rightarrow \infty} v(t)=\lim _{t \rightarrow \infty} \sqrt{\frac{m g}{k}} \tanh (\sqrt{\frac{k g}{m}} t)\) b. Find the terminal velocity for the jumper in Exercise 96 \((m=75 \mathrm{kg} \text { and } k=0.2)\) c. How long does it take for any falling object to reach a speed equal to \(95 \%\) of its terminal velocity? Leave your answer in terms of \(k, g,\) and \(m\) d. How tall must a cliff be so that the BASE jumper \((m=75 \mathrm{kg}\) and \(k=0.2\) ) reaches \(95 \%\) of terminal velocity? Assume that the jumper needs at least \(300 \mathrm{m}\) at the end of free fall to deploy the chute and land safely.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.