■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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