Question 942422
1 - cot^4 (theta) =    2csc^2 (theta) - csc^4 (theta)
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(1-cot^2)(1+cot^2) = csc^2[2-csc^2]
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(1-cot^2)(csc^2) = csc^2(2-csc^2)
1-cot^2 = 2 - csc^2
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-cot^2 = 1 - csc^2
csc^2-cot^2 = 1
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1 = 1
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Cheers,
Stan H.
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