$1-\cos\alpha$1-\cos\alpha

$\displaystyle \frac{\cos\alpha}{\tg\alpha}$\displaystyle \frac{\cos\alpha}{\tg\alpha}

$\displaystyle \frac{\sin\alpha}{\cos\alpha}$\displaystyle \frac{\sin\alpha}{\cos\alpha}

$\tg\alpha \cdot \sin\alpha$\tg\alpha \cdot \sin\alpha