Suppose that XXX and YYY are random variables such that Corr(X,Y)=−1\corr{X}{Y} = -1Corr(X,Y)=−1 and σY>σX\sigma_Y > \sigma_XσY>σX. Find Corr(X+Y,X−Y)\corr{X+Y}{X-Y}Corr(X+Y,X−Y).
