﻿ If θ lies in the first quadrant and cos θ = 8/17, then the value of cos (300 +θ) + cos (450 – θ) + cos (1200 – θ) is : Kaysons Education

# If θ lies In The First Quadrant And Cos θ = 8/17, Then The Value Of Cos (300 +θ) + Cos (450 – θ) + Cos (1200 – θ) Is

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## Question

### Solution

Correct option is

Now the given expression is equal to

cos 300 cos θ – sin 300 sin θ + cos 450 cos θ + sin 450 sin θ + cos 1200 cos θ + sin 1200 sin θ

= cos θ (cos 300 + cos 450 + cos 1200) – sin θ (sin 300 – sin 45 – sin 1200)

=

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