# Maximum area and minimum perimeter.

• Dec 8th 2009, 01:00 PM
Rumor
Maximum area and minimum perimeter.
Here's another problem I'm stuck on:

"A rectangle has one side on the x-axis, one side on the y-axis, one vertex at the origin and one on the curve y=e^-2x (greater than or equal to) 0. Find the

a) Maximum area
b) Minimum perimeter."

Here's a picture of the curve:

http://i23.photobucket.com/albums/b3...ra/example.jpg

Any help on how to do this would be appreciated!
• Dec 8th 2009, 01:36 PM
skeeter
Quote:

Originally Posted by Rumor
Here's another problem I'm stuck on:

"A rectangle has one side on the x-axis, one side on the y-axis, one vertex at the origin and one on the curve y=e^-2x (greater than or equal to) 0. Find the

a) Maximum area
b) Minimum perimeter."

Here's a picture of the curve:

http://i23.photobucket.com/albums/b3...ra/example.jpg

Any help on how to do this would be appreciated!

\$\displaystyle A(x) = xe^{-2x}\$

\$\displaystyle P(x) = 2(x + e^{-2x})
\$

take the derivatives and optimize ...