1. The problem statement, all variables and given/known data [tex]\int\int(rsin2\vartheta)drd\vartheta[/tex] sorry i dont see how to put the bounds in but they are 0<[tex]\vartheta[/tex]<[tex]\pi[/tex]/2 and 0<r<2acos[tex]\vartheta[/tex] 2. Relevant equations I know that r=sin[tex]\vartheta[/tex] 3. The attempt at a solution Im really not sure where to start my text is terrible. I really dont know how to treat it with the double angle. thanks for any help sorry meant to put converting polar to rectangular.