■葉序らせん(その28)
A(0,0,1/2)
B(0,0,−1/2)
C(0,√3/2,0)
D(√(2/3),√3/6,0)
E(−√(2/3),√3/6,0)
A(0,0,1/2)
C(0,√3/2,0)
D(√(2/3),√3/6,0)
F(α,β,γ)
G(ξ,η,ζ)
y軸の回りに回転させると
A(−s/2,0,c/2)
B(s/2,0,c/2)
C(0,√3/2,0)
D(c√(2/3),√3/6,s√(2/3))
E(−c√(2/3),√3/6,s√(2/3))
A(−s/2,0,c/2)
C(0,√3/2,0)
D(c√(2/3),√3/6,s√(2/3))
F(αc−γs,β,αs+γc)
G(ξc−ζs,η,ξs+ζc)
O(0,y,0)
△ADFの重心Hは
H((α+√(2/3))/3,(β+√3/6)/3,(γ+1/2)/3)
G(ξ,η,ζ)はC+2CHで与えられる.
CH=((α+√(2/3))/3,(β+√3/6)/3−√3/2,(γ+1/2)/3)
2CH=(2(α+√(2/3))/3,2(β+√3/6)/3−√3,2(γ+1/2)/3)
C+2CH=(2(α+√(2/3))/3,2(β+√3/6)/3−√3/2,2(γ+1/2)/3)
AF^2=1
CF^2=1
DF^2=1
α=2√6/9=2√2/3√3
β=2√12/9=4/3√3
γ=√6α−1/2=12/9−1/2=5/6
ξ=2(5/3・√(2/3))/3=10/9・√(2/3)
η=2(4/3√3+1/2√3)/3−√3/2=11/9√3−3/2√3=−5/18√3
ζ=2(γ+1/2)/3=8/9
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