Question

Given `sin60^circ=sqrt3/2` and `cos60^circ=1/2`, how do you find `cos30^circ`?

Answer 1

`cos(30^@)=sqrt(3)/2`

Explanation:

Based on the image below and the basic definitions of `sin` and `cos`
we know that `cos(theta)=sin(90^@-theta)`

Therefore `cos(30^@)=sin(60^@)=sqrt(3)/2`