Cos = 5/13 найти tg sin < 0 - Все ответы

Cos = 5/13 найти tg
sin < 0

Решение.

sin= $\sqrt{1- cos^{2} } = \sqrt{1- (\frac{5}{13}) ^{2} } = \sqrt{1- \frac{25}{169} } = \sqrt{ \frac{169}{169}- \frac{25}{169} } = \sqrt{ \frac{169-25}{169} }$
sin= $\sqrt{ \frac{144}{169} } = \frac{12}{13}$
Т.к. sin<0 то sin=-<img src="https://tex.z-dn.net/?f=+%5Cfrac%7B12%7D%7B13%7D+" id="TexFormula3" title=" \frac{12}{13} " alt=" \frac{12}{13} " align="absmiddle" class="latex-formula">

tg= $\frac{sin}{cos} =- \frac{12}{13} * \frac{13}{5} = -\frac{12}{5}$