Kąt α jest ostry i cosα= 4/5. Wtedy

$\displaystyle \tg\alpha= \frac{3}{4}$\displaystyle \tg\alpha= \frac{3}{4}

$\displaystyle \tg\alpha= \frac{4}{5}$\displaystyle \tg\alpha= \frac{4}{5}

$\displaystyle \sin\alpha= \frac{1}{5 }$\displaystyle \sin\alpha= \frac{1}{5 }

$\displaystyle \sin\alpha= \frac{4}{5}$\displaystyle \sin\alpha= \frac{4}{5}