SOLUTION: How do I verify the identity of 2/(1+cosx)-tan^2(x/2) = 1?

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Question 889156: How do I verify the identity of 2/(1+cosx)-tan^2(x/2) = 1?
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
note that tan^2(x/2) = (1 - cos(x)) / (1 + cos(x))
this is half angle trig identity squared
2 / (1 + cos(x)) - (1 - cos(x)) / (1 + cos(x)) =
2 - 1 + cos(x) / (1 + cos(x)) =
(1 + cos(x)) / (1 + cos(x)) = 1