NCERT Exercise 8.3 - Q2 - Introduction to Trigonometry
Question: Write all the other trigonometric ratios of ∠A in terms of sec A.
Answer: sin A = sqrt(sec^2 A - 1)/sec A, cos A = 1/sec A, tan A = sqrt(sec^2 A - 1), cot A = 1/sqrt(sec^2 A - 1) and cosec A = sec A/sqrt(sec^2 A - 1).
Full step-by-step NCERT solution with diagrams on Something by Zero.