Find the volume of the solid

Question

Using disks or washers, find the volume of the solid obtained by rotating the region bounded by the curves y=√(x-1), y=0, x=2 and x=5 about the x-axis 

Answer 1

Volume v = π∫₂⁵((x - 1)dx = π(x - 1)²/2₂⁵ = 7.5π