Finding value to calculate volume
Given let W be the region obtained by rotating D around Y axis.
A) Find the volume of W
B) Find, if possible, the a values so that the volume of W is a minimum, and a maximum
C) Find, if possible, the a values so that the volume of W is a minimum, and a maximum
Well, what I've done so far is finding the inner and outer radius to calculate the volume in terms of Y. The inner radius would be be and the outer would be , which is a evaluated in the parabola. Then, the volume would be .
And that's the function that I have to differentiate to find its maxima and minima, which, after differentiating, is 1/a. Is ok what am I doing? How can I go on?