Question

How do you simplify `cos (sin^-1(1/2))`?

Answer 1

`+-sqrt 3 / 2`

Explanation:

Let `a = sin^(-1)(1/2)`.

a is in either in first quadrant or the second quadrant.

Accordingly, `cos a = +- sqrt3 / 2`..

So, `cos sin^(-1)(1/2) = cos a = +-sqrt 3 / 2`. .