■等面単体の体積(その286)

P0(√(1/2),0,√(1/2),1,√3

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

P2(√2,√3,0,0,0)

P3(√8,0,0,0,0)

P4(√(9/2),0,√(9/2),0,0)

P5(√2,0,√2,2,0)

  P0P1=P1P2=P2P3=P3P4=P4P5=√5

  P0P2=P1P3=P2P4=P3P5=√8

  P0P3=P1P4=P2P5=3

  P0P4=P1P5=√8

  P0P5=√5

を満たす.

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P0(√(1/2),0,√(1/2),1,√3)

P1(a,b,c,d,e)

P2(√2,√3,0,0,0)

P3(√8,0,0,0,0)

P4(√(9/2),0,√(9/2),0,0)

P5(√2,0,√2,2,0)

とおいて,

  P0P1=P1P2=P2P3=P3P4=P4P5=√5

  P0P2=P1P3=P2P4=P3P5=√8

  P0P3=P1P4=P2P5=3

  P0P4=P1P5=√8

  P0P5=√5

を満たすものを探す.

  (a−√(1/2))^2+b^2+(c−√(1/2))^2+(d−1)^2+(e−√3)^2=5

  (a−√2)^2+(b−√3)^2+c^2+d^2+e^2=5

  (a−√8)^2+b^2+c^2+d^2+e^2=8

  (a−√(9/2))^2+b^2+(c−√(9/2))^2+d^2+e^2=9

  (a−√2))^2+b^2+(c−√2))^2+(d−2)^2+e^2=8

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P1=P2+sP1P0=(√2,√3,0,0,0)+s(√(1/2),0,√(1/2),1,√3)

P1=P3+sP1P0=(√8,0,0,0,0)+s(√(1/2),0,√(1/2),1,√3)

P1=P4+sP1P0=(√(9/2),0,√(9/2),0,0) +s(√(1/2),0,√(1/2),1,√3)

P1=P5+sP1P0=(√2,0,√2,2,0)+s(√(1/2),0,√(1/2),1,√3)

となる新たなP1を選ぶ.

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