■平方根と連分数(その43)
α=[a0:a1,a2,・・・]
λ=[an+1:an+2,an+3,・・・]+[0:an,an-1,・・・,a1]
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[2:1,2,1,2,1,・・・]=1+√3
[0:2,1,2,1,2,1,・・・]=1/(1+√3)=(-1+√3)/2
[3:2,1,2,1,2,1,・・・]=(5+√3)/2=(55+11√3)/22
[0:3:2,1,2,1,2,1,・・・]=2/(5+√3)=(5-√3)/11=(10-2√3)/22
λ=[3:2,1,2,1,2,1,・・・]+[0:3,2,1,2,1,2,1,・・・]=(65+11√3)/22 (OK)
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x=[2:1,2,2,1,2,・・・],y=1/x
x=2+1/(1+1/(2+1/x))
x=2+1/(1+x/(2x+1))
x=2+(2x+1)/(3x+1)=(8x+3)/(3x+1)
3x^2-7x-3=0
x={7+(85)^1/2}/6
y=6/{7+(85)^1/2}={(85)^1/2-7}/6
λ=(85)^1/2/3=(9・9+4)/3
λ=(9・Q^2+4)^1/2/Q
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x=[2:1,1,2,2,1,1,2,・・・],y=1/x
x=2+1/(1+1/(1+1/(2+1/x))
x=2+1/(1+1/(1+x/(2x+1))
x=2+1/(1+(2x+1)/(3x+1))
x=2+(3x+1)/(5x+2)
x=(13x+5)/(5x+2)
5x^2-11x-5=0
x={11+(221)^1/2}/10
y=10/{11+(221)^1/2}={(221)^1/2-11}/10
λ=(221)^1/2/5=(9・25+4)^1/2/5にならない
λ=(9・Q^2-4)^1/2/Qになっている
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x=[2:1,1,1,2,2,1,1,1,2,・・・],y=1/x
x=2+1/(1+1/(1+1/(1+1/(2+1/x))
x=2+1/(1+1/(1+1/(1+x/(2x+1))
x=2+1/(1+1/(1+(2x+1)/(3x+1))
x=2+1/(1+(3x+1)/(5x+2)
x=2+(5x+2)/(8x+3)
x=(21x+8)/(8x+3)
8x^2-18x-8=0
x={9+(145)^1/2}/8
y=8/{9+(145)^1/2}={(145)^1/2-9}/8
λ=(145)^1/2/4=(9・16+1)^1/2/4
λ=(9・Q^2+4)^1/2/Q・・・にならない
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