Question

How do you evaluate sine, cosine, tangent of `300^circ` without using a calculator?

Answer 1

`cos 300 = 1/2`
`sin 300 = - sqrt3/2`
`tan 300 = - (4sqrt3)/3`

Explanation:

Use trig table of special arcs and unit circle -->
`cos 300 = cos (-60 + 360) = cos (-60) = cos (60) = 1/2`
`sin 300 = sin (-60 + 360) = sin (-60) = - sin 60 = - sqrt3/2`
`tan 300 = sin/(cos) = (-2/sqrt3)(2/1) = -4/(sqrt3) = - (4sqrt3)/3`