Help with question: 2014 trial (1 Viewer)

[Itsduhtom]

The diagram shows the shaded region enclosed by the curve y = √(x-1), the y axis, and the lines y=1 and y=3
Find the volume of the solid when the shaded region is rotated about the y axis

 

[Drongoski]

 

[dan964]

Firstly make x the subject.
x=y^2+1

Since I am not sure what level you are doing:
just evaluate therefore the integral between 1 and 3 and it should be fine by putting in its usual form of π ∫ x^2 dy
i.e. the above
(someone is faster at typing)