I have to find the volume of the given solid "enclosed by the cylinders z=x^2, y=x^2, and the planes z=0, y=4. But I'm not sure it makes sense. z=x^2 and y=x^2 aren't cylinders, though, they are parabolas. And they don't actually "enclose" any area, do they? Maybe I'm drawing it wrong, but I just can't make sense of it.
Maybe an easier question for someone to answer would be, what should I set as my limits of integration? I know y should be between 0 and 4, and x should be between -2 and 2, but I guess I don't know what function I'm integrating.
The point of this section was also to integrate using functions as bounds (for 1 or both variables), as opposed to numbers.
Both of these represent the same region. In some problems, changing the order of integration can make it easier to evaluate the integrals. In this case it doesn't matter too much.