[tex]0^{o} < \alpha < 90^{o}\\\\cos\alpha = \frac{3}{5}\\\\sin^{2}\alpha + cos^{2}\alpha = 1\\\\sin^{2}\alpha = 1-cos^{2}\alpha = 1 - (\frac{3}{5})^{2} = \frac{25}{25} - \frac{9}{25} = \frac{16}{25}\\\\sin\alpha = \sqrt{\frac{16}{25}} = \frac{4}{5}\\\\tg\alpga = \frac{sin\alpha}{cos\alpha} = \frac{\frac{4}{5}}{\frac{3}{5}} = \frac{4}{3}[/tex]
[tex]ctg\alpha =\frac{cos\alpha}{sin\alpha} = \frac{\frac{3}{5}}{\frac{4}{5}} = \frac{3}{4}[/tex]
