sin π/3=√3/2
[tex] \frac{AB}{sin C}=2\cdot R \\ \\R= \frac{AB}{2\cdot sin C} = \frac{6}{2\cdot \frac{ \sqrt{3}}{2} } = \frac{6}{ \sqrt{3}} } \\ \\ \frac{6}{ \sqrt{3} }= \frac{6 \sqrt{3} }3} =2 \sqrt{3} \\ \\ R=2 \sqrt{3}cm [/tex]
se face rationalizarea