# Double Integrals

• Mar 24th 2010, 02:15 PM
jason0
Double Integrals
I have two questions that I've been having problems with, mainly finding the bounds of x and y, if anyone could help me with that part of the problem it would be greatly appreciated, thanks

http://i39.tinypic.com/nh074p.png

for this one, since it's an average value, do the bounds have to be numbers and not functions for both x and y?

http://i43.tinypic.com/dnbj88.png
• Mar 24th 2010, 02:37 PM
11rdc11
Quote:

Originally Posted by jason0
I have two questions that I've been having problems with, mainly finding the bounds of x and y, if anyone could help me with that part of the problem it would be greatly appreciated, thanks

http://i39.tinypic.com/nh074p.png

for this one, since it's an average value, do the bounds have to be numbers and not functions for both x and y?

http://i43.tinypic.com/dnbj88.png

for the first one

$\int^{\frac{1}{4}}_{0}\int^{\sqrt{x}}_{2x} ye^x dydx$
• Mar 24th 2010, 02:45 PM
11rdc11
The formula is

$\frac{1}{area} \int\int f(x,y) dydx$
• Mar 24th 2010, 05:56 PM
jason0
Quote:

Originally Posted by 11rdc11
for the first one

$\int^{\frac{1}{4}}_{0}\int^{\sqrt{x}}_{2x} ye^x dydx$

i got the second one but am still struggling with this one, can anyone help me out with the actual integration?