# Thread: Differentials word problem help

1. ## Differentials word problem help

Hey guys, cant seem to build up the formula for this question. Trying to evaluate dy and delta y for the indicated values...

A cube with sides 10inches long is covered with a coat of fiberglass 0.2 inch thick. Use differentials to estimate the volume of the fiberglass shell.

2. My guess would be using the volume formula and the upper limit is 10.02 and lower limit is 10 would to be find the antiderivative for the formula and plug in the new limits and such and F(b) - F(a), sorry for not being so clear

Something like this I assume since the volume formula of a cube is

$a^3$

$\int a^3$

$\frac{a^4}{4}$

3. We haven't gotten into integrals yet. So im assuming there's another way?