Question

$\frac{1 + tga}{1 + ctga}$
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Answer 1

$\frac{1+tg\alpha }{1+Ctg\alpha }=\frac{1+tg\alpha }{1+\frac{1}{tg\alpha}}=\frac{1+tg\alpha}{\frac{tg\alpha+1 }{tg\alpha}}= \frac{tg\alpha(1+tg\alpha)}{tg\alpha+1 }=\boxed{tg\alpha}$