So this is the average value of our function. One third times 12 which is equal to four. You can find the average value of a function over a closed interval by using the mean value theorem for integrals.
The best way to understand the mean value theorem for integrals is with a diagram look at the following figure.
Plug the upper limit of integration 3 into the formula you obtained in Step 2. Find the Average Value of the Function fxsinx 0pi. The average value of our function over this interval is equal to four. E3x is e 3 x and e 3x is e 3 x.