Graphing density probability functions

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Homework Statement


let Y1 and Y2 have the joint probability density function given by:
8y1y22, 0 <= y1 <= 1, 0 <= y2 <= 1, y12 <= y2

0, otherwise



Homework Equations


Basic integrals? if they are even needed.


The Attempt at a Solution


I attempted it, by assuming 0 - 1 for y1 and y2 and got a square from 1 to 1 on y1 to y2

But assuming it's a square, it must be independent, and I continued the work and it is NOT independent, so the square shape would be wrong?

I'm not too sure on how to graph multi-variable functions like this in probability.
 
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It's only the part of the square where (y1)^2<=y2. You didn't say what the problem is, but I think you just want to show the integral of 8*y1*y2^2 over that region is 1, right? Can you show us how you tried to do that?
 
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