Solution:
(i) Option (B) is correct.
Proof:
When you take 9 outside, it becomes
9 sec2A – 9 tan2A
= 9 (sec2A – tan2A)
= 9×1 = 9 (∵ sec2 A – tan2 A = 1)
As a result, 9 sec2A – 9 tan2A = 9
(ii) Option (C) is correct
Proof:
(1 + tan θ + sec θ) (1 + cot θ – cosec θ)
We even know that, tan θ = sin θ/cos θ
sec θ = 1/ cos θ
cot θ = cos θ/sin θ
cosec θ = 1/sin θ
Substituting the above values into the problem gives:
= (1 + sin θ/cos θ + 1/ cos θ) (1 + cos θ/sin θ – 1/sin θ)
Simplifying the provided equation as,
= (cos θ +sin θ+1)/cos θ × (sin θ+cos θ-1)/sin θ
= (cos θ+sin θ)2-12/(cos θ sin θ)
= (cos2θ + sin2θ + 2cos θ sin θ -1)/(cos θ sin θ)
= (1+ 2cos θ sin θ -1)/(cos θ sin θ) (Since cos2θ + sin2θ = 1)
As a result,