Given: L.H.S. =

Since we know

So L.H.S. =

Multiplying Numerator & Denominator with sin θ -1 + cos θ we get

L.H.S. =

⇒

Since sin² θ + cos² θ = 1

⇒

⇒

⇒

L.H.S. = R.H.S.

Hence Proved