# double integration?

• December 2nd 2010, 07:48 PM
weissman91
double integration?
http://einstein.math.fsu.edu:9080/te...2.question.gifany help would be greatly appreciated thankyou
• December 2nd 2010, 09:16 PM
pickslides
Yep, integrate twice here, look at this example, could be helpful.

( 843, #35) The average value of a function f(x,y) over a rectangle R
• December 3rd 2010, 05:33 AM
HallsofIvy
The "average value" of f(x,y) over $a\le x\le b$, $c\le y\le d$ is
$\frac{\int_{x=a}^b\int_{y= c}^d f(x,y)dy dx}{(b-a)(d-c)}$.

That is, it is the integral of the function over the region divided by the area of that region.