consider the following regions.\nfind the volume of the solid generated by revolving the specified region…

consider the following regions.\nfind the volume of the solid generated by revolving the specified region about the given line.\n$r_1$ about $x = 0$
Answer
Explanation:
Step1: Set up the disk - washer method formula
The region $R_1$ is bounded by $y = x$, $y = 1$, and $x = 0$. When revolving about the $y$-axis ($x = 0$), we use the disk - washer method. For a vertical axis of revolution, if we integrate with respect to $y$, the volume $V=\pi\int_{a}^{b}[R(y)]^{2}dy$. Here, for $y\in[0,1]$, the right - most curve is $x = y$.
Step2: Apply the integral formula
The volume formula becomes $V=\pi\int_{0}^{1}y^{2}dy$.
Step3: Integrate the function
Using the power rule for integration $\int y^{n}dy=\frac{y^{n + 1}}{n+1}+C$ ($n\neq - 1$), we have $\int_{0}^{1}y^{2}dy=\left[\frac{y^{3}}{3}\right]_{0}^{1}$.
Step4: Evaluate the definite integral
$\left[\frac{y^{3}}{3}\right]_{0}^{1}=\frac{1^{3}}{3}-\frac{0^{3}}{3}=\frac{1}{3}$. Then $V=\pi\times\frac{1}{3}=\frac{\pi}{3}$.
Answer:
$\frac{\pi}{3}$