Question 1084031: I need to solve the problem in this link please
https://drive.google.com/open?id=0B2SbxAb-ajtfRW00d2NCZWdFSW8 Answer by ikleyn(52866) (Show Source):
The length of the rectangle is 2x (from -x to +x). It is "horizontal" dimension.
The height of the rectangle is f(x) = . It is "vertical" dimension.
The area of the rectangle is A(x) = = .
To find the maximum, take the derivative and equate it to zero:
= 16 - 12x^2 = 0.
====> = ====> x = = = .
You calculate maximal area A(x) by substituting x = .
