1+ sinθ1− sinθ=tan2(π4+θ2)
Prove the following
1.(1−sin2A)sec2A=1
2.sec4θ−sec2θ=tan4θ+tan2
3.(secθ−tanθ)2=1−sinθ1+sinθ
4.tanθ+secθ−1tanθ−secθ+=1+sinθcosθ