Question

If `(cos θ + sec θ) = 5/2` then (cos²θ + sec²θ) = ?

विकल्प

• `17/4`

• `21/4`

• `29/4`

• `33/4`

Answer 1

`bb(17/4)`

Explanation:

`(cos θ + sec θ)^2 = (5/2)^2`

⇒ `cos^2θ + sec^2θ + 2 cos θ sec θ = 25/4`

⇒ `(cos^2θ + sec^2θ) + 2 = 25/4`

⇒ `(cos^2θ + sec^2θ) = (25/4 - 2) = 17/4`