■DE群多面体の面数公式(その887)

D5,ρについて

P0(0,0,0,0,0)

P1(1,0,0,0,0)

P2(1,1/√3,0,0,0)

P3(1,1/√3,1/√6,0,0)

P4(1,1/√3,1/√6,1/√10,0)

P5(1,1/√3,1/√6,1/√10,3/√10)

  cosθ=10/{6+10}^1/2{10+10/9}^1/2=10/4・3/10=3/4***

  cosθ=√10/3/{10+10/9}^1/2=√10/3・√9/100=1/√10

σについて

P0(0,0,0,0,0)

P1(1,0,0,0,0)

P2(1,1/√3,0,0,0)

P3(1,1/√3,1/√6,0,0)

P4(1,1/√3,1/√6,1/√2,0)

P5(1,1/√3,1/√6,1/√2,1/√2)→E5に一致

  cosθ=2/{6+2}^1/2{2+2}^1/2=1/2√2***

  cosθ=√2/{2+2}^1/2=1/√2

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