If the angle θ= –60º, find the value of cosθ. - Geometry Mathematics 2

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Sum

If the angle θ= –60º, find the value of cosθ.

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Solution

We know that,

cos(-α) = cosα

 cos(-60°) = cos60°

 cos(-60°) = 1/2

 cos(-60°) = cosθ = 1/2

 cosθ = 1/2

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2015-2016 (March) Set A

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