Question

Упростите выражение Sin 2a/1+cos 2a

Answer 1

$\sf \dfrac{\sin2\alpha}{1+\cos2\alpha}=\dfrac{2\sin\alpha\cos\alpha}{1+2\cos^2\alpha-1}=\dfrac{2\sin\alpha\cos\alpha}{2\cos^2\alpha}=\dfrac{\sin\alpha}{\cos\alpha}={\rm tg}\,\alpha$