# Math Help - Find Mass of Rod?

1. ## Find Mass of Rod?

A rod with constant cross section A and length L lies along the x-axis from x= 0 to x = L.
The density of the rod depends only on x and is given by rho(x) = e^(2x). Calculate the mass
of the rod.

Am I right doig this?

integral of A*e^(2x) dx = (A*(e^((2)(L)))/2-(e^((2)(0)))/2)

2. ## Re: Find Mass of Rod?

lots of ((( ))) to sift through, but I do believe you have the right idea ...

$m = A \int_0^L e^{2x} \, dx = \left[\frac{e^{2x}}{2} \right]_0^L = \frac{e^{2L}-1}{2}$