Q) Evaluate 2sec2 θ + 3 cosec2 θ – 2 sin θ cos θ if θ = 450.
Ans: Since θ = 450, sec 450 = √2, cosec 450 = √2, sin 450 = 
; cos 450 =
2sec2 θ + 3 cosec2 θ – 2 sin θ cos θ
= 2 (√2)2 + 3 (√2)2 – 2 
= 4 + 6 – 1 = 9
Q) Evaluate 2sec2 θ + 3 cosec2 θ – 2 sin θ cos θ if θ = 450.
Ans: Since θ = 450, sec 450 = √2, cosec 450 = √2, sin 450 = ; cos 450 =
2sec2 θ + 3 cosec2 θ – 2 sin θ cos θ
= 2 (√2)2 + 3 (√2)2 – 2
= 4 + 6 – 1 = 9