Verify the identities.

Question

). (secθ-1)(secθ+1)=tan^2θ

). sin2θ/1-cos2θ=cotθ



). sec^2 θ-2tanθ=(1-tanθ)^2

Answer 1

1) sec²x-1 = tans²x

2) 2sin x cos x/(1-cos²x-sin²x) =cos/sin x = cot x

3) 1-2 tan x+tan²x=(1-tan x)²