Thread: How to get the critical numbers?

Question:


Attempt:



After this step i dont know how to simplify?

Please anwer in steps
Thank you.

You can multiply the right side by [2(4-x^2)^(1/2)]/[2(4-x^2)^(1/2)]
you should end up with [4-2x^2]/[(4-x^2)^(1/2)]