# How do you find all critical numbers of the function #f(x)=x^(4/5)(x-4)^2#?

##### 1 Answer

#### Explanation:

Critical points are points in the domain where the derivative is equal to zero or where the derivative is not defined.

**Derivative Equal to Zero:**

The derivative can be found by using the power rule and the chain rule.

Now we set this equal to zero:

We get:

**Derivative Not Defined:**

The only possible case where

Therefore we set

Therefore, the derivative is not defined at

**Conclusion**

The critical points of this function are