1. The problem statement, all variables and given/known data Find I(z) (moment of inertia about the z-axis) bounded by the cone z=sqrt(3(X^2 + y^2)) and the sphere with radius a. Density is inversely proportional to the distance from the z-axis. 2. Relevant equations double integration 3. The attempt at a solution basicall, I set up my integral, solved it and got a negative number and was hoping somebody could let me know if my original integral is wrong. it is: [tex]\int\int\int(B^3)(sin\Phi)^3[/tex] d[tex]B[/tex]d[tex]\Phi[/tex]d[tex]\Theta[/tex] please ignore the exponent in the above intergral. I can't figure out this website! It's supposed to be on the same level as the rest of the integral to show you the order I am intergrating with respect to. Thanks! I put the limits of B from 0 to a, of Phi from 0 to (pi/6) and the limits of Theta from 0 to 2(pi). Intergrate first with respect to B then, phi, then theta. I'm basically trying to use spherical coordinates to solve this integral. Thanks!