Решите пожалуйста, срочно

Решите задачу:

$\frac{1}{ctg \alpha} + \frac{\cos\alpha}{1+\sin\alpha} = tg \alpha + \frac{\cos\alpha}{1+\sin\alpha} = \frac{\sin\alpha}{\cos\alpha} + \frac{\cos\alpha}{1+\sin\alpha} =\frac{\sin\alpha(1+\sin\alpha)+\cos^2\alpha}{\cos\alpha(1+\sin\alpha)} = \\ = \frac{\sin\alpha+\sin^2\alpha+\cos^2\alpha}{\cos\alpha(1+\sin\alpha)} = \frac{\sin\alpha+1}{\cos\alpha(1+\sin\alpha)} =\frac{1}{\cos\alpha}$

$\frac{1}{\cos\beta} - \cos\beta = \frac{1-\cos^2\beta}{\cos\beta} = \frac{1-(1-\sin^2\beta)}{\cos\beta} = \frac{\sin^2\beta}{\cos\beta} = \sin\beta\cdot\frac{\sin\beta}{\cos\beta} = \sin\beta\cdot tg\beta$