Question

if cos x + sin x = root 2 cos x prove that cos x minus sin x equal to root 2 sin x

Answer 1

Let cos x-sin x=t
(Cos x+sin x) ^2 +(^cos x-sin x) ^2 =2cos^2 x +t^2
(2sin^2 x+2cos^2 x) =2cos^2 x +t^2
2-2cos^2 x=t^2
2 sin^2 x=t^2
t=+/-v2sin x

Answer 2

i hope its the right answer