please help!
The average value of cosx on the interval [-3,5] is...?
I looked in my book and asked a friend but nobody understands...the answer is supposed to be (sin3 + sin5)/8...
In general (assuming the integral can be done, etc.) the average (mean) value of a function f(x) over the interval (a, b) is:
$\displaystyle \overline{f} = \frac{1}{b - a} \int_a^b dx f(x)$
You can find this under the heading "mean value theorem for integration" or something similar.
-Dan