三十五角形
2 cos  2 π 35 + ω ⋅ 2 cos  32 π 35 + ω 2 ⋅ 2 cos  22 π 35 = − 7 + 49 5 + 15 14 ( 5 − 5 ) + 2 14 ( 5 + 5 ) − 3 3 ( 7 + 7 5 + 14 ( 5 − 5 ) + 2 14 ( 5 + 5 ) ) i 8 3 2 cos  2 π 35 + ω 2 ⋅ 2 cos  32 π 35 + ω ⋅ 2 cos  22 π 35 = − 7 + 49 5 + 15 14 ( 5 − 5 ) + 2 14 ( 5 + 5 ) + 3 3 ( 7 + 7 5 + 14 ( 5 − 5 ) + 2 14 ( 5 + 5 ) ) i 8 3 {\displaystyle {\begin{aligned}2\cos {\frac {2\pi }{35}}+\omega \cdot 2\cos {\frac {32\pi }{35}}+\omega ^{2}\cdot 2\cos {\frac {22\pi }{35}}=&{\sqrt[{3}]{\tfrac {{-7+49{\sqrt {5}}+15{\sqrt {14\left(5-{\sqrt {5}}\right)}}+2{\sqrt {14\left(5+{\sqrt {5}}\right)}}}-3{\sqrt {3}}\left(7+7{\sqrt {5}}+{\sqrt {14\left(5-{\sqrt {5}}\right)}}+2{\sqrt {14\left(5+{\sqrt {5}}\right)}}\right)i}{8}}}\\2\cos {\frac {2\pi }{35}}+\omega ^{2}\cdot 2\cos {\frac {32\pi }{35}}+\omega \cdot 2\cos {\frac {22\pi }{35}}=&{\sqrt[{3}]{\tfrac {{-7+49{\sqrt {5}}+15{\sqrt {14\left(5-{\sqrt {5}}\right)}}+2{\sqrt {14\left(5+{\sqrt {5}}\right)}}}+3{\sqrt {3}}\left(7+7{\sqrt {5}}+{\sqrt {14\left(5-{\sqrt {5}}\right)}}+2{\sqrt {14\left(5+{\sqrt {5}}\right)}}\right)i}{8}}}\\\end{aligned}}}