Question

if sina/x = cosa/y prove that sina-cosa = x-y)/root over (x^2 +y^2)

Answer 1

(Sina)/x=(cosa)/y =( square root of sin^2a+cos^2a)/square root of x^2+y^2
=1/sq.root of (x^2+y^2)
That is sina=x/Sq. root of(x^2+y^2) and
cosa=y/Sq. root of (x^2+y^2)
Hence,sina- cosa=(x-y)/Sq. root of (x^2+y^2)