Question

(secA + tanA) (1 − sinA) = ______.

विकल्प

• sec A

• sin A

• cosec A

• cos A

Answer 1

(secA + tanA) (1 − sinA) = cos A.

Explanation:

(secA + tanA) (1 − sinA)

= `(1/cosA+sinA/cosA)(1-sinA)`

= `((1+sinA)/cosA)(1-sinA)`

= `(1-sin^2A)/(cosA)`

= `(cos^2A)/cos A`

= cosA

Hence, alternative cosA is correct.