Hi, the question is attached below.

Attempt at solutionSurface area = 2*pi*r*ds = 2*pi*integral (from 1 to 2) of x^3*sqrt(1+9x^4)dx

I ended up with 199.4804797 as my answer.

However, I'm having trouble finding the area of revolution using the parametrization method. What is r(t)?