Question

For ∠θ express all the Trigonometric ratios in terms of sec θ.

Answer 1

(i) sin² θ + cos² θ = 1

⇒ sin² θ = 1 – cos² θ

(ii) Cos θ = 1/secθ

(iii) ∵ 1 + tan² θ = sec² θ

or, tan² θ = sec² θ – 1

or, tan θ = √(sec²θ - 1)

(iv) cot θ = 1/tanθ

= 1/√(sec²θ - 1)

(v) cosec θ = 1/sinθ