f(r)=r/(10r^2+7) find the critical numbers. I found the derivative to be -10r^2+7/(10r^2+7)^2 and now I am stuck. What do I do next?

2 answers

so, the critical numbers are the values where f'(r) = 0, right?

A fraction is zero if its numerator is zero.

So, what is r if

7 - 10r^2 = 0?
I made that seem a lot more complicated than it was! Thank you for your help!