Suppose that X and Y are positive and X>Y. Explain why we must have x^2>y^2.

Guest Jun 2, 2017

#1**+1 **

Suppose that X and Y are positive and X>Y. Explain why we must have x^2>y^2.

Well you could just say it is obvious but I guess that would not get you any brownie points.

What about:

Let X=Y+n where X,Y and n are all positive

\(X^2=(Y+n)^2=Y^2+n^2+2nY=Y^2+\text{a positive number}\\ \therefore\\ X^2>Y^2\)

Melody
Jun 2, 2017