Surface Integrals Prolbem? If the mass per unit area of a surface is given by ρ=xy, find the mass if S is the part of the cylinder x^2+z^2=25 which is in the first octant and contained within the cylinder x^2+y^2=16.
So here was my attempt.
I parametrized the curve.
x^2+z^2=25
r(u, v) = <5cos(u), v, 5sin(u)>
I then plugged into the...