先化简在求值(x/x-1-1/x²-x)÷(x+1),其中x=1/2
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先化简在求值(x/x-1-1/x²-x)÷(x+1),其中x=1/2
先化简在求值
(x/x-1-1/x²-x)÷(x+1),其中x=1/2
先化简在求值(x/x-1-1/x²-x)÷(x+1),其中x=1/2
[x/(x-1)-1/(x²-x)]÷(x+1)
=[x²/x(x-1)-1/x(x-1)]÷(x+1)
=(x²-1)/x(x-1)÷(x+1)
=(x+1)(x-1)/x(x-1)÷(x+1)
=(x+1)/x÷(x+1)
=1/x
=1/(1/2)
=2
答:
x=1/2
(x/x-1-1/x²-x)÷(x+1)
=[x/(x-1)-1/(x²-x)]÷(x+1)
=[x²/(x²-x)-1/(x²-x)]÷(x+1)
=(x-1)(x+1)/[x(x-1)]÷(x+1)
=1/x
=2