Question 643075
transform sin theta tan theta + cos theta into sec theta 
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sin(x)*tan(x) + cos(x) = sec(x)
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sin(x)*(sin(x)/cos(x)) + cos(x) = sec(x)
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sin^2(x)/cos(x) + cos(x) = sec(x)
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Multiply thru by cos(x) to get:
sin^2(x) + cos^2(x) = 1
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1 = 1
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Cheers,
Stan H.
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