<PRE><B>Question 943942</B>
cos^2(x)-tan^2(x) 
-------------------- =Cot^2(x)-sec^2(x)
    sin^2(x)

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Note:: sin^2 is a common denominator for cos^2 and for tan^2::
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[cos^2/sin^2 - tan^2/sin^2] = cot^2 - sec^2
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[cot^2 - (1/cos^2)] = cot^2 - sec^2
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cot^2 - sec^2 = cot^2 - sec^2
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Cheers,
Stan H.
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