Question

Calculate the volume of the solid obtained by rotating around the x-axis:
a) 0<= x <= 1 and sqrt(x) <= y <= 3
b) x² <= y <= x
c) 0 <= y <= x and x²+y² <= 2
d) y >= x² and x² + y² <= 2
e) 1/x <= y <= 1 and 1<= x <=2
f) x² + (y-2)² <= 1

folks, those exercises I couldn't solve. My answers is different from the book's answers. I hope to see yours. Thank you very much.