1. The problem statement, all variables and given/known data Find any critical numbers of the function 2. Relevant equations g(t) = sqrt (4-t) , t < 3 3. The attempt at a solution I'm not really sure how to find a critical number when square roots are involved. I do know typically when finding the critical number you find the derivative of the equation and then set that equal to 0. However I ended up with the derivative dx = 4 sqrt (4-t) / 4-t. I tried setting that to 0 but got no where.