I am having quite a bit of trouble with triple integrals and I keep coming to this problem.

Find the volume between the plane and the - plane, for and

So I started with the bounds which are:

And so the triple integral should look like:

After simplifying I ended up with:

And After evaluating I ended up with . I am not sure where I went wrong but the answer is supposed to be 1.

I just wanted to say thanks for everyone that has been helping me the past few days with this kind of stuff, I appreciate it a lot.