Questions: R is the region bounded by the functions f(x)=1+x^2 and the g(x)=sqrt(x+1) and the lines x=0 and x=3.
Represent the volume when R is rotated around the y-axis.
Volume =∫ from 0 to 3 square dx
Transcript text: $R$ is the region bounded by the functions
$\mathrm{f}(\mathrm{x})=1+x^{2}$ and the $\mathrm{g}(\mathrm{x})=\sqrt{x+1}$ and the lines $\mathrm{x}=0$ and $\mathrm{x}=3$.
Represent the volume when $R$ is rotated around the $y$-axis.
Volume $=\int_{0}^{3}$ $\square$ $d x$
Use pi for " $\pi$ " and sqrt(x) for " $\sqrt{x}$ "
Solution
Solution Steps
Step 1: Define the Functions
We are given two functions that bound the region \( R \):
\( f(x) = 1 + x^2 \)
\( g(x) = \sqrt{x + 1} \)
Step 2: Set Up the Volume Integral
To find the volume of the solid formed by rotating the region \( R \) around the \( y \)-axis, we use the method of cylindrical shells. The volume \( V \) is given by the integral:
\[
V = \int_{0}^{3} 2\pi x (f(x) - g(x)) \, dx
\]
Step 3: Calculate the Volume
Substituting the functions into the integral, we have:
\[
V = \int_{0}^{3} 2\pi x \left((1 + x^2) - \sqrt{x + 1}\right) \, dx
\]
After evaluating this integral, we find:
\[
V = \frac{1021\pi}{30}
\]
Final Answer
The volume of the solid formed by rotating the region \( R \) around the \( y \)-axis is
\[
\boxed{V = \frac{1021\pi}{30}}
\]