SOLUTION: If cot(x/2)=a, what is sin(x) ?

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Question 1105023: If cot(x/2)=a, what is sin(x) ?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If cot(x/2)=a, what is sin(x) ?
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cot(x/2) = sqrt[(1+cos(x))/(1-cos(x)]
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a^2 = (1+cos(x))/(1-cos(x))
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a^2 = [(1+cos(x)(1-cos(x))/(1-cos(x))^2]
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a^2 = sin^2(x)/(1-cos(x))^2
a = sin(x)/(1-cos(x))
sin(x) = a/(1-cos(x))
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Cheers,
Stan H.
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