Question 825681
(1/(1-sinx)-sinx/(1+sinx))
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 rewrite the expression in terms of the tan(x)
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(1+sinx -sinx(1-sin(x))/(1-sin^2(x))
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[1+sin(x)-sin(x)+sin^2(x)]/cos^2(x)
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= [1+sin^2(x)]/cos^2(x)
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= sec^2(x) + tan^2(x)
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Cheers,
Stan H.