已知X^2+X-1=0,求X(1-2/1-X)÷(X+1)-X(X^2-1)/X^2-2X+1的值
已知X^2+X-1=0,求X[1-﹙2/1-X)]÷(X+1)-X(X^2-1)/X^2-2X+1的值...
已知X^2+X-1=0,求X[1-﹙2/1-X)]÷(X+1)-X(X^2-1)/X^2-2X+1的值
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∵x²+x-1=0
∴x²+x=1
x[1-﹙2/1-X)]÷(X+1)-X(X^2-1)/X^2-2X+1
=x[(1-x-2)/(1-x)]÷(x+1)-x(x-1)(x+1)/(x-1)²
=x(-1-x)/(1-x)÷(x+1)-x(x+1)/(x-1)
=x(x+1)/(x-1)(x+1)-x(x+1)/(x-1)
=x/(x-1)-(x²+x)/(x-1)
=(x-1)/(x-1)
=1
∴x²+x=1
x[1-﹙2/1-X)]÷(X+1)-X(X^2-1)/X^2-2X+1
=x[(1-x-2)/(1-x)]÷(x+1)-x(x-1)(x+1)/(x-1)²
=x(-1-x)/(1-x)÷(x+1)-x(x+1)/(x-1)
=x(x+1)/(x-1)(x+1)-x(x+1)/(x-1)
=x/(x-1)-(x²+x)/(x-1)
=(x-1)/(x-1)
=1
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x²+x-1=0
x²+x=1
x[1-﹙2/1-X)]÷(X+1)-X(X^2-1)/X^2-2X+1
=x[(1-x-2)/(1-x)]÷(x+1)-x(x-1)(x+1)/(x-1)²
=x(-1-x)/(1-x)÷(x+1)-x(x+1)/(x-1)
=x(x+1)/(x-1)(x+1)-x(x+1)/(x-1)
=x/(x-1)-(x²+x)/(x-1)
=(x-1)/(x-1)
=1
x²+x=1
x[1-﹙2/1-X)]÷(X+1)-X(X^2-1)/X^2-2X+1
=x[(1-x-2)/(1-x)]÷(x+1)-x(x-1)(x+1)/(x-1)²
=x(-1-x)/(1-x)÷(x+1)-x(x+1)/(x-1)
=x(x+1)/(x-1)(x+1)-x(x+1)/(x-1)
=x/(x-1)-(x²+x)/(x-1)
=(x-1)/(x-1)
=1
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