# computing derivatives using a given graph

I know $f'(1/2)= 1$ because the professor did that part of the problem in class. But unfortunately I just cannot see the logic to complete the rest of the problem. This problem is supposed to be really easy.

-
I had to rollback to include the image link, because the question/answer made no sense without it. –  Arkamis Nov 2 '12 at 18:04

Try applying the chain rule. For example, $\dfrac{d}{dx}{f\left(e^{x}\right)}=e^x\cdot f'(t)\lvert_{t=e^x}\;.$