π 12 = π 2 ⋅ 6 ⋅ 180 ∘ π 2 e x = π 2 ⋅ 6 ⋅ 2 ⋅ 2 ⋅ 5 3 ⋅ 3 ⋅ π ⋅ π 2 ⋅ 2 ⋅ 5 ⋅ 3 ⋅ 3 = π 6 {\displaystyle {\frac {\pi }{12}}={\frac {\pi }{2\cdot 6}}\cdot {\frac {180^{\circ }}{\pi }}{2ex}={\frac {\cancel {\pi }}{{\cancel {2}}\cdot {6}}}\cdot {\frac {{\cancel {2}}\cdot {2}\cdot {5}{3}\cdot {3}\cdot }{\cancel {\pi }}}\cdot {\frac {\pi }{{\cancel {2}}\cdot {2}\cdot {\cancel {5}}\cdot {\cancel {3}}\cdot 3}}={\frac {\pi }{6}}}
