Question

If cos(x) = (1/4), where x lies in quadrant 4, how do you find sin(x)?

Answer 1

`sinx=-sqrt(15)/4`

Explanation:

`sinx=+-sqrt(1-cos^2x)`

Since x lies in quadrant 4, the values of sinx are negative
so

`sinx=-sqrt(1-1/16)=-sqrt(15/16)=-sqrt(15)/4`