I'm stuck with these derivative problems. I've tried all the methods that I know and haven't gotten anything.

1. Find f'(x) where f(x) = . Then find f'(5)

2. Find f'(x) where f(x) =

3. Find f'(x) where f(x) =

4. Find f'(9) where f(x) =

5. Find f'(x) where f(x) = 12/(t^5)