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Discussion Response Post to: doubt 4

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Marshall Eriksen (1586)

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total posts: 1312
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2cos(60-x)cos(60+x) 2cosx=1
[cos(120) + cos(-2x)] 2cosx = 1
[-1/2 + cos 2x] 2cosx = 1
-cosx + 2cosxcos2x = 1
2cosxcos2x - cosx =1
cos 3x + cos x - cos x = 1
cos 3x = 1
Thus 3x = 0
x = 0

x = 2 pi n

I Dont Think I Have Made Any Mistake But If i Have...Do Let Me Know...Rate Me If My Solution Is Adequate
* I Have used cos(-x) = cos x a lot*

Sometimes One Dream Is Enough To Light Up The Entire October Sky.... First Year Mechanical Engineering Veermata Jijabai Technological Institute

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