You can put this solution on YOUR website! cosy/(1-siny)= (1+siny)/cosy
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Cross-multiply to get:
cos^2(y) = 1-sin^2(y)
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cos^2(y) = cos^2(y)
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Solution y can have any value that does not make cos(y) = 0
and sin(y) = 1
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Cheers,
Stan H.