Question

What is the exact value of cos(–60º)?

Answer 1

The exact value is. +1/2.

Answer 2

The exact value of
`cos(-60\°)=(1/2)`

Explanation:

we know that

The angle
`-60\°` belong to the fourth quadrant

The function cosine is positive in the first and in the fourth quadrant

so

`cos(-60\°)=cos(60\°)`

Remember that

`cos(60\°)=(1/2)`

so

`cos(-60\°)=(1/2)`