This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
The critical numbers are those that make the function equal to 0. If we factor this, we will have

f(x) = x (x+√12) (x-√12)

So, the critical numbers are 0, -√12, and +√12.