Math Problem Statement

Solve it

Find the volume of the solid of revolution generated by rotating the region under the graph of y = √x from x = 0 to x = 1 about the x-axis.

Solution

To solve the problem of finding the volume of the solid of revolution, we use the disk method, since the solid is generated by revolving the region under the curve y=xy = \sqrt{x} about the xx-axis from x=0x = 0 to x=1x = 1.


Step-by-step solution:

  1. Volume formula for the disk method: The formula for the volume of a solid of revolution about the xx-axis is: V=πab[f(x)]2dxV = \pi \int_a^b [f(x)]^2 \, dx Here:

    • f(x)=xf(x) = \sqrt{x}
    • The bounds are a=0a = 0 and b=1b = 1.
  2. Set up the integral: Substituting f(x)=xf(x) = \sqrt{x} into the formula, we get: V=π01(x)2dxV = \pi \int_0^1 (\sqrt{x})^2 \, dx

  3. Simplify the integrand: Since (x)2=x(\sqrt{x})^2 = x, the integral becomes: V=π01xdxV = \pi \int_0^1 x \, dx

  4. Evaluate the integral: The integral of xx is: xdx=x22\int x \, dx = \frac{x^2}{2} Applying the bounds 00 to 11, we compute: [x22]01=122022=12\left[ \frac{x^2}{2} \right]_0^1 = \frac{1^2}{2} - \frac{0^2}{2} = \frac{1}{2}

  5. Compute the volume: Multiply the result by π\pi: V=π12=π2V = \pi \cdot \frac{1}{2} = \frac{\pi}{2}


Final Answer:

The volume of the solid of revolution is: π2\boxed{\frac{\pi}{2}}

Would you like a detailed explanation of any step? 😊


Related Questions:

  1. What is the difference between the disk and washer methods in solids of revolution?
  2. How would the integral change if the region was rotated about the line y=1y = 1 instead of the xx-axis?
  3. Can you compute the volume if the function is y=x2y = x^2 instead of y=xy = \sqrt{x}?
  4. What if the bounds were changed from x=0x = 0 to x=2x = 2? How would the volume calculation change?
  5. How do we apply the shell method for revolving the same region?

Tip:

When using the disk method, always remember to square the function f(x)f(x) before integrating to account for the area of the circular cross-sections.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Calculus
Solid of Revolution
Integration

Formulas

V = π ∫[a, b] (f(x))^2 dx

Theorems

Disk Method

Suitable Grade Level

College-Level or Advanced High School Calculus