How abt assuming four points (a cos\theta , b sin \theta), (a cos\theta ,-b sin \theta),(-a cos\theta , b sin \theta),(-a cos\theta ,-b sin \theta)
to be the vertices of that rectangle...then area =4absin\theta cos\theta=2absin 2\theta
and then maximizing the area ? So 2ab ?
I tried to register with my real name but somebody had already taken it.:mad: I don't like adding numbers after my name. Google Spider is one of the usernames which no body has ever used on any internet forum. That's why I have started using this as my "internet name".
Some people have done...
I think both your equations correct, you just did something wrong with the calculations. :smile:
BTW, what's mathematica ? Are you using a http://en.wikipedia.org/wiki/Mathematica" to solve these equations ?