Can you provide the actual and entire problem statement?
i tried to traw the projection of the top interval in the z-y plane
so we have a circle
but the radius changes from x to .
which is not possible because when we scan the ring it goes from the biiger radius to the smaller one.
then i thought to try in anyway ,and i wrote the integral in polar
but i dont know how mathmatickly to change the intervals?
how to solve it in a polar way?