1) Find the Critical Numbers for

after all the work is done I get

There aren't any critical numbers is what I got but I'm not sure.

2) Find the Critical Numbers for

I get as a critical number but I'm not sure if it's right or the only answer

3) Find the Absolute max and min for

in the interval

after simplifying the derivative for it I get:

I don't know what to do with it since I am bad with trig functions in these types of problems.