1,解方程:x方-2x-1=0 2,先化简在求值,(1+x-3/x+3)除以2x/x方-9,其中x=根号3+3

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1,解方程:x方-2x-1=02,先化简在求值,(1+x-3/x+3)除以2x/x方-9,其中x=根号3+31,解方程:x方-2x-1=02,先化简在求值,(1+x-3/x+3)除以2x/x方-9,其

1,解方程:x方-2x-1=0 2,先化简在求值,(1+x-3/x+3)除以2x/x方-9,其中x=根号3+3
1,解方程:x方-2x-1=0 2,先化简在求值,(1+x-3/x+3)除以2x/x方-9,其中x=根号3+3

1,解方程:x方-2x-1=0 2,先化简在求值,(1+x-3/x+3)除以2x/x方-9,其中x=根号3+3
解1:x²-2x-1=0
x²-2x=1
x²-2x+1=2
(x-1)²=2
x-1=±√2
x-1=√2或x-1=-√2
x1=1+√2
x2=1-√2
解2:原式=[1+(x-3)/(x+3)]÷[2x/(x²-9)]
=[2x/(x+3)]÷[2x/(x+3)(x-3)]
=[2x/(x+3)]×[(x+3)(x-3)/2x]
=x-3
当x=√3+3时
原式=√3+3-3=√3

1,解方程:x方-2x-1=0
(x-1)²=2
x-1=±根号(2)
x=1±根号2
(1+x-3/x+3)除以2x/x方-9
=(1+(x-3)/(x+3))*(x+3)(x-3)/2x
=2x/(x+3)*(x+3)(x-3)/2x
=x-3
=根号3

1.x1=1+根号2
x2=1-根号2
2.1+x-3/x+3=2x/x+3
2x/x方-9=2x/(x+3)*(x-3)
最后化简为x-3
所以等于根号3