Hello, I've been studying double integrals over non-rectangular regions and have been having a bit of trouble but think I've cracked it. However, the book answer and me disagree on the following question; Mathematica agrees with me but I thought maybe I was using the wrong region. The question is:

Find the volume of the solid which is below the plane and above the xy-plane and bounded by .

The region, R, in the xy-plane I'm evaluating over is and the final answer I get is . Whereas the book gets .

Could somebody verify if I'm using the right region and what the actual answer is?

Thanks,

triptyline