Question
upstudy study bank question image url

\begin{tabular}{l} Use the shell method to find the volume of the solid generated by revolving the region bounded by the graphs of the equations about the \\ line \( x=5 \). \\ \( \qquad \begin{aligned} y=\sqrt{x} \\ y=0 \\ x=4\end{aligned} \) \\ \hline\end{tabular}

Ask by Johnson Bob. in the United States
Feb 25,2025

Upstudy AI Solution

Tutor-Verified Answer

Answer

The volume of the solid is \( \frac{416\pi}{15} \) cubic units.

Solution

We wish to find the volume of the solid formed by revolving the region bounded by   y = √x,  y = 0,  and  x = 4 about the vertical line x = 5 using the shell method. Step 1. Sketch the region. • The curve y = √x starts at (0,0) and rises to (4,2) since √4 = 2. • The line y = 0 is the x-axis. • The vertical line x = 4 is the right boundary. Thus, the region lies between x = 0 and x = 4 (with the left boundary implicitly at x = 0 because y = √x and y = 0 meet at x = 0). Step 2. Set up the shell method. Since we are revolving about the vertical line x = 5, it is natural to use vertical slices (dx). A typical slice at position x (where 0 ≤ x ≤ 4) has: • Height = √x (from y = 0 to y = √x). • Distance from the axis of rotation = radius = (5 − x). • Thickness = dx. The lateral surface area of the cylindrical shell is 2π(radius)(height) and its volume is 2π(5 − x)(√x) dx. Step 3. Write the integral for the volume. The volume V is given by   V = ∫[x=0 to 4] 2π (5 − x)(√x) dx     = 2π ∫₀⁴ (5√x − x√x) dx. Step 4. Evaluate the integral. First, note that x√x = x^(3/2). So,   V = 2π [ 5∫₀⁴ x^(1/2) dx − ∫₀⁴ x^(3/2) dx ]. Recall the power rule for integration:   ∫ x^n dx = x^(n+1)/(n+1). Thus,   ∫ x^(1/2) dx = (2/3)x^(3/2)  and  ∫ x^(3/2) dx = (2/5)x^(5/2). Substitute these into the integral:   V = 2π [ 5*(2/3)x^(3/2) − (2/5)x^(5/2) ] evaluated from 0 to 4,     = 2π [ (10/3)x^(3/2) − (2/5)x^(5/2) ] from x = 0 to x = 4. Now, evaluate at x = 4 (the lower limit gives 0): • 4^(3/2) = (4^(1))·(4^(1/2)) = 4·2 = 8. • 4^(5/2) = 4^(2)·(4^(1/2)) = 16·2 = 32. So,   V = 2π [ (10/3)*8 − (2/5)*32 ]     = 2π [ (80/3) − (64/5) ]. Find a common denominator for the terms inside the bracket:   (80/3) = (80×5)/(3×5) = 400/15  and  (64/5) = (64×3)/(5×3) = 192/15. Thus,   (80/3) − (64/5) = (400 − 192) / 15 = 208/15. Finally, multiply by 2π:   V = 2π (208/15) = (416π)/15. Step 5. Write the final answer. The volume of the solid is (416π)/15 cubic units.

Answered by UpStudy AI and reviewed by a Professional Tutor

error msg
Explain
Simplify this solution

Extra Insights

To find the volume of the solid generated by revolving the region bounded by the graphs of \( y = \sqrt{x} \), \( y = 0 \), and \( x = 4 \) about the line \( x = 5 \) using the shell method, we first need to identify the relevant dimensions and shape of the shell. The region we’re revolving is from \( x = 0 \) to \( x = 4 \), and the height of the shell at any point \( x \) is given by the function \( y = \sqrt{x} \). The formula for the volume \( V \) using the shell method is: \[ V = 2\pi \int_{a}^{b} (radius)(height) \, dx \] Here, the radius is the distance from the shell to the line \( x = 5 \), which is \( 5 - x \). The height is \( y = \sqrt{x} \). Thus, we have: \[ V = 2\pi \int_{0}^{4} (5 - x)(\sqrt{x}) \, dx \] Now, we will compute the integral: 1. Distribute \( (5 - x) \) with \( \sqrt{x} \): \[ V = 2\pi \int_{0}^{4} (5\sqrt{x} - x\sqrt{x}) \, dx \] or: \[ = 2\pi \int_{0}^{4} (5\sqrt{x} - x^{3/2}) \, dx \] 2. Evaluate the integral: - Integrate \( 5\sqrt{x} \): \[ \int 5\sqrt{x} \, dx = 5 \cdot \frac{2}{3} x^{3/2} = \frac{10}{3} x^{3/2} \] - Integrate \( x^{3/2} \): \[ \int x^{3/2} \, dx = \frac{2}{5} x^{5/2} \] 3. Combine and evaluate: \[ V = 2\pi \left[ \left( \frac{10}{3} x^{3/2} - \frac{2}{5} x^{5/2} \right) \Bigg|_{0}^{4} \right] \] Evaluate at \( x = 4 \): \[ V = 2\pi \left[ \left( \frac{10}{3} (4)^{3/2} - \frac{2}{5} (4)^{5/2} \right) - 0 \right] \] \[ = 2\pi \left[ \frac{10}{3} (8) - \frac{2}{5} (32) \right] \] \[ = 2\pi \left[ \frac{80}{3} - \frac{64}{5} \right] \] Finding a common denominator (15): \[ = 2\pi \left[ \frac{400}{15} - \frac{192}{15} \right] \] \[ = 2\pi \left[ \frac{208}{15} \right] \] \[ = \frac{416\pi}{15} \] Thus, the volume \( V \) of the solid generated by revolving the given region around the line \( x = 5 \) is: \[ \boxed{\frac{416\pi}{15}} \]

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy