# How do you differentiate #f(x)=(1/(3x))*x*e^x-x*cosx# using the product rule?

##### 1 Answer

Dec 13, 2016

#### Answer:

Please see below.

#### Explanation:

Simplify first

We do not need the product rule for the first term, although you may use it if you like.

For the second term, we need the product rule. (unless we do something unusual.)

# = cosx-xsinx#

Putting it all together,