# How do you find the intervals of increasing and decreasing using the first derivative given #y=-(x^2+8x+12)#?

##### 1 Answer

Feb 6, 2017

The interval of increasing is

The interval of decreasing is

#### Explanation:

We calculate the first derivative and then build a sign chart

Let

Critical point when

Let construct the sign chart

The interval of increasing is

The interval of decreasing is