# How do you find the relative extrema for #f(x)=(x^4)+(4x^3)-12#?

##### 1 Answer

Dec 30, 2017

#### Explanation:

and ** #f# is continuous at #x_0=0#** so

so

#x<-3# #=># #f(x)>f(-3)=-39# - (#f# decreasing)#x>=-3# #=># #f(x)>=f(-3)=-39# - (#f# increasing)

As a result

(you can mention that