Question

PLEASE HELP! URGENT! MEDAL!

Answer 1

@Hero @SolomonZelman

Answer 2

Average rate of change can be found with:
\[(f(\pi/2)-f(0)/((\pi/2)-0)\]
Instantaneous rate of change is the derivative of the function:
\[f'(x)=\cos(x)\]
The idea is to solve the first one and then set the derivative equal to that answer to find the value of x. Let me know if you want me to work out more of it, I tried to leave as much for you to do as I could.

Answer 3

Oh, thank you!