Question

How do you solve and find the value of `cos(arccos(-1/2))`?

Answer 1

`- 1/2`

Explanation:

Use trig table of special arcs and unit circle -->
`cos x = - 1/2` --> 2 solution arcs -->
arc `x = (2pi)/3` and arc `x = (4pi)/3`
`cos ((2pi)/3) = cos ((4pi)/3) = - 1/2`