1.[a/(ab-b²)-b/(a²-ab)]÷[1+(a²+b²)/(2ab)],其中a=-1+根号3,b=-1-根号32.解关于x的方程:(x+1)/(a+b)+(x-1)/(a-b)=2a/(a²-b²) (a≠0)3.已知A·B=2x+8,A=3x/(x-2)-x/(x+2),求B

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1.[a/(ab-b²)-b/(a²-ab)]÷[1+(a²+b²)/(2ab)],其中a=-1+根号3,b=-1-根号32.解关于x的方程:(x+1)/(a+b)+(x-1)/(a-b)=2a/(a²-b²) (a≠0)3.已知A·B=2x+8,A=3x/(x-2)-x/(x+2),求B
1.[a/(ab-b²)-b/(a²-ab)]÷[1+(a²+b²)/(2ab)],其中a=-1+根号3,b=-1-根号3
2.解关于x的方程:(x+1)/(a+b)+(x-1)/(a-b)=2a/(a²-b²) (a≠0)
3.已知A·B=2x+8,A=3x/(x-2)-x/(x+2),求B

1.[a/(ab-b²)-b/(a²-ab)]÷[1+(a²+b²)/(2ab)],其中a=-1+根号3,b=-1-根号32.解关于x的方程:(x+1)/(a+b)+(x-1)/(a-b)=2a/(a²-b²) (a≠0)3.已知A·B=2x+8,A=3x/(x-2)-x/(x+2),求B
1.[a/(ab-b²)-b/(a²-ab)]÷[1+(a²+b²)/2ab],其中a=-1+根号3,b=-1-根号3
=[a/b(a-b)-b/a(a-b)]÷(2ab+a²+b²)/2ab
=(a²-b²)/ab(a-b)÷(a+b)²/2ab
=2/(a+b)
=2/(-1+√3-1-√3)
=2/(-2)
=-1
2.解关于x的方程:
(x+1)/(a+b)+(x-1)/(a-b)=2a/(a²-b²) (a≠0)
(x+1)(a-b)+(x-1)(a+b)=2a
xa+a-xb-b+xa-a+xb-b=2a
2xa=2a+2b
∴x=(a+b)/a
3.已知A·B=2x+8,A=3x/(x-2)-x/(x+2),求B
∵A·B=2x+8,
∴B=(2x+8)÷A
=(2x+8)÷[3x/(x-2)-x/(x+2)],
=(2x+8)÷(3x²+6x-x²+2x)/(x-2)(x+2)
=2(x+4)*(x-2)(x+2)÷(2x²+8x)
=(x-2)(x+2)/x
∴B=(x²-4)/x