# Homework Help: Surface area of rotation

1. Jan 26, 2014

### californicate

1. The problem statement, all variables and given/known data
Obtain the surface area when the curve y=ex, 0≤x≤1, is rotated about the x-axis

2. Relevant equations
Surface Area = 2∏ab x√(1+(dy/dx)2)dx

3. The attempt at a solution
I started with the the equation, Surface Area = 2∏01 x√(1+e2x)dx. However, whichever way I try to integrate I end up getting stuck. By substitution, Nothing ends up working so that the integral becomes simpler, much less only according to one variable. By parts, I just end up with messier and messier integrals. How should I approach this problem?

Thanks!
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Jan 26, 2014

### Saitama

Hi californicate! Welcome to PF!

Your relevant equation doesn't look right to me. :)

3. Jan 26, 2014

### californicate

So should the x inside the integral be replaced with an f(x)? That's the equation the prof gave in class, however in examples he switched back and forth between using f(x) and x. I'll ask about it next class.

Thanks!

4. Jan 26, 2014