■ABCからDEへ(その52)
D6,ρについて
P0(0,0,0,0,0,0)
P1(1,0,0,0,0,0)
P2(1,1/√3,0,0,0,0)
P3(1,1/√3,1/√6,0,0,0)
P4(1,1/√3,1/√6,1/√10,0,0)
P5(1,1/√3,1/√6,1/√10,1/√15,0)
P6(1,1/√3,1/√6,1/√10,1/√15,2/√3)
cosθ=10/{6+10}^1/2{10+15}^1/2=1/2***
cosθ=15/{10+15}^1/2{15+3/4}^1/2=6/√63
cosθ=√3/2/{15+3/4}^1/2=√3/63=1/√21
σについて
P0(0,0,0,0,0,0)
P1(1,0,0,0,0,0)
P2(1,1/√3,0,0,0,0)
P3(1,1/√3,1/√6,0,0,0)
P4(1,1/√3,1/√6,1/√10,0,0)
P5(1,1/√3,1/√6,1/√10,3/√10,0)
P6(1,1/√3,1/√6,1/√10,3/√10,1/√2)
cosθ=10/{6+10}^1/2{10+15}^1/2=1/2***
cosθ=10/{6+10}^1/2{10+10/9}^1/2=5/2・3/10=3/4
cosθ=10/9/{10+10/9}^1/2{10/9+2}^1/2=10/9・3/10/√28/3=1/√28
cosθ=√2/{10/9+2}^1/2=√2/√28/9)=3/√14
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(その41)(その42)に一致
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