# Is #f(x)=(x-3)(x+3)(x-2)# increasing or decreasing at #x=1#?

##### 1 Answer

Apr 5, 2018

Decreasing. Instantaneous rate of change -10

#### Explanation:

To find if the function is decreasing, we need the first derivative. The easiest way to do this is to expand into the cubic and then use the power rule:

Taking the derivative:

This "function" tells us the slope at x. So, plug in x=1:

Since