Prove each of the following identities:
(sec2 θ – 1)(cosec2 θ – 1) = 1
Consider the left – hand side:
L.H.S. = (sec2 θ – 1)(cosec2 θ – 1)
= (tan2θ) × cot2θ (∵ 1 + tan2 θ = sec2 θ and 1 + cot2 θ = cosec2 θ)
= 1
= R.H.S.
Hence, proved.