SOLUTION: Prove the identity (1+ sec x)/(sec x) = 2cos^2 (1/2) x

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Question 450825: Prove the identity
(1+ sec x)/(sec x) = 2cos^2 (1/2) x
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Prove the identity
(1+ sec x)/(sec x) = 2cos^2 (1/2) x
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= [(1/sec)+1) = 2cos^2[(1/2)x]
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= (cos + 1)/2 = cos^2[(1/2)x)]
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cos[(1/2)x] = sqrt[(cos(x)+1)/2]
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Cheers,
Stan H.