Consider 4 tan 2 θ – = 4 tan 2 θ – 4 sec 2 θ = 4(tan 2 θ – sec 2 θ) = 4( – 1) ( ∵ 1 + tan 2 θ = sec 2 θ) = – 4

Write the value of .

Consider 4 tan² θ – = 4 tan² θ – 4 sec² θ

= 4(tan² θ – sec² θ)

= 4( – 1) (∵1 + tan² θ = sec² θ)

= – 4