# Math Help - Help rectangle in circle

1. ## Help rectangle in circle

Please how do I find the max size that the RED rectangles in this circle can be?

2. This seems like it should lead somewhere.

1) Pick one red rectangle.

2) Draw a radius to each of its two distant corners.

3) Define the area of the rectangle as a function of the interior angle $\theta$ so defined. Pretty obviously, $0 < \theta < \frac{\pi}{2}$. The area of the rectangle is zero at either exteme.

Now what?

Other ideas?

3. Originally Posted by wolfhound
Please how do I find the max size that the RED rectangles in this circle can be?
I tink I would impose a coordinate system at the center of the circle such that $x^2+y^2=1$. This leaves a pile of ways to solve this problem.