i need some answers??

[waterloo699]

A rectangle is inscribed in a circle radius of 5m. Determine the maximum possible area for such a rectangle.

 

[Gene]

Well, it is intuitively obvious that it is a square. To prove that:
It is W wide by H high.
W²+H²=10²
The area is
A = WH = W*sqrt(100-W²)
Set the derivitive dA/dW = 0 and solve for W