How do I switch order of integration of [math]\int _0^2\int _ {2x} ^4\int _0^ {\sqrt {y^2-4x^2}} \,dz\,dy\,dx[/math] to [math]dx\,dy\,dz[/math] without sketching a 3D graph? What hormonal contraceptive pill are you on, and how has it affected you?