Question

Cos2teta-sin2teta=0 prove it

Answer 1

Answer:

Here your answer

Step-by-step explanation:

Let a, b, c be lengths of right angled triangle

By definition

sinθ=b/c(hypotenuseopposite side)

cosθ=a/c(hypotenuseadjacent side)

sin2θ+cos2θ=c2b2+c2a2=c2a2+b2

From Pythagoras theorem

c2=a2+b2

∴c2a2+b2=1

sin2θ+cos2θ=1