Question

How do you find the exact value of cos (-5pi/3)?

Answer 1

`1/2`

Explanation:

Start like this `cos ((-5pi)/3) = cos (2pi -(5pi)/3)` because adding `2pi` does not change the value of a trignometric function.So, `2pi-(5pi)/3 = pi/3`

`cos ((pi)/3)` equals `1/2`
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