■葉序らせん(その33)

 ここで座標変換を行いたい.

  A(−s/2,−√3/5,c/2)

  B(s/2,−√3/5,c/2)

  C(0,3√3/10,0)

  D(c√(2/3),−√3/30,s√(2/3))

  E(−c√(2/3),−√3/30,s√(2/3))

  F(αc−γs,β−y,αs+γc)

  G(ξc−ζs,η−y,ξs+ζc)

  O(0,0,0)

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cos(∠AOB)=(−s2/4+3/25+c^2/4)/{1/4+3/25)

s^2=3/5,c^2=2/5を代入すると

cos(∠AOB)=(−3/20+3/25+2/20)/(1/4+3/25)

=7/37

cos(∠DOE)=(−2c^2/3+1/300+2s^2/3)/(2/3+1/300)

=(−4/15+1/300+6/15)/(2/3+1/300)

=41/201

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