Question

How do you rrite the trigonometric function sec x in terms of sin x?

Answer 1

We know that `sec x = 1/cos x` (Reciprocal identity)

We also know that `cosx = sin(pi/2-x) = sqrt(1-sin^2x)` (Cofunction identity and Pythagorean identity.)

So we could write `sec x = 1/sin(pi/2-x)` and we could write `sec x = 1/sqrt(1-sin^2x)`