# What is the surface area of the solid created by revolving #f(x) =2x+5 , x in [1,2]# around the x axis?

##### 1 Answer

Jan 5, 2017

We need to calculate the area of te curved surface and the two end circles.

#### Explanation:

The end circles have radii

The are of the curved surface may be calculated by considering an infinitesimal ring of radius

Now,

So we have to evaluate the integral

The total area is then