[tex]A \ triunghi\ = \frac{AB*AC*sin(BAC)}{2} = 4 (cm^{2} ) \\
\\
\frac{AB*AC*sin(BAC)}{2} = 4 \rightarrow sin(BAC)= \frac{4*2}{AB*AC } \rightarrow sin(BAC)= \frac{8}{4*6} \rightarrow \\ \\
sin(BAC)= \frac{8}{8*3} \rightarrow sin(BAC)= \frac{1}{3}
[/tex]