i hav another small question about calculus.please help...
F= (x^3+2xy^2,y^3+2yz^2,z^3+2zx^2) is a vector field.
fine integral( F.dS) on a sphere of radius R centered at the origin.
I am not sure about what dS is. I think it should be a unit vector perpendicular to the surface u r calculating, is it right?
I let n = ( 0, 0, 1) and try to integrate, but there are z and x , how to operate this?