π 12 = π 2 ⋅ 6 ⋅ 180 ∘ π = π 2 ⋅ 6 ⋅ 2 ⋅ 2 ⋅ 5 ⋅ 3 ⋅ 3 ⋅ π = 90 ∘ 6 = 15 ∘ {\displaystyle {\frac {\pi }{12}}={\frac {\pi }{2\cdot 6}}\cdot {\frac {180^{\circ }}{\pi }}={\frac {\cancel {\pi }}{{\cancel {2}}\cdot {6}}}\cdot {\frac {{\cancel {2}}\cdot {2}\cdot {5}\cdot {3}\cdot {3}\cdot }{\cancel {\pi }}}={\frac {90^{\circ }}{6}}={15^{\circ }}}
