[tex]x este in cadranu III unde sin x \ \textless \ 0., deci.sin x=
- \sqrt{1- cos^{2}x
[/tex]
Deci sin x = -[tex] \sqrt{1- cos^{2} x} = - \sqrt{1- ( \frac{ 2\sqrt{6} }{6} ) ^{2} [/tex]
Obtinem: sin x= -[tex] \sqrt{1- \frac{24}{25} }= -\sqrt{ \frac{1}{25} } = - \frac{1}{5}. [/tex]
