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

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Answer 1 · 2016-05-06T14:52:20

$+-sqrt 3 / 2$

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

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

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

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

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