Area Between Curves: Calculate Volume Revolved Around Y Axis

[Aerosion]

Homework Statement

This is so basic and yet I'm not getting it.

Find the volume of the solid when the region enclosed is revolved arond the y axis.

x = \sqrt{1 + y}
x=0, y=3

Homework Equations

The Attempt at a Solution

So I first graphed the thing, finding that the enclosed area was between y=1 and y=3. I took the volumne of the equation, or A=pi *\sqrt{1 + y}^2. I then took the integral, pi * \int_{1}^{3} 1 + y dy, coming out with 6*pi. My book says this isn't right. Did I do anything wrong? Use the wrong formula?

 

[AKG]

The enclosed area is not between y=1 and y=3.

 

[Aerosion]

Oh wait...I think I got it.

I was graphing with the equation set equal to x, when it should have been set equal to y. This would make \int_{-1}^{3} 1 + y dy, which, when multiplied by pi, would get 8*pi.

Thanks.