Prove that (1+sinA-cosA/1+sinA+cosA)2 = 1-cosA/1+cosA . . .

Question : Prove that (1+sinA-cosA/1+sinA+cosA)2 = 1-cosA/1+cosA

Doubt by Jaskirat

Solution : 

[Using Identity : (x+y+z)²=x²+y²+z²+2xy+2yz+2zx]

[Using Identity : sin²θ+cos²θ]

= RHS

LHS=RHS

Hence Proved.