# R.O.C of trig functions

DespicableMe

## Homework Statement

Determine the average rate of change of the function y = 2cos (x - pi/3) + 1 for the following internal:
pi/2 < x < 5pi/4

## Homework Equations

AROC = [ f(x2) - f(x1) ] / x2) - x1

## The Attempt at a Solution

For an approx. value, I would set the calculator in radian mode and just plug everything into the equation, right?
Where I'm stuck is how to get an EXACT answer.