# How do you find the critical numbers for #cos (x/(x^2+1))# to determine the maximum and minimum?

##### 1 Answer

Jul 30, 2016

#### Answer:

So the critical point is

#### Explanation:

**Critical point : It is the point where the first derivative zero or it does not exist.**

First find the derivative , set it to 0 solve for x.

And we need to check is there a value of x which makes the first derivative undefined.

Set dy/dx=0

So the critical point is