已知x²+x-1=0,求x(1-2除以1-x)除以(x+1)-x(x²-1)除以x平方-2x+1的值
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![已知x²+x-1=0,求x(1-2除以1-x)除以(x+1)-x(x²-1)除以x平方-2x+1的值](/uploads/image/z/1055708-44-8.jpg?t=%E5%B7%B2%E7%9F%A5x%26%23178%3B%2Bx-1%3D0%2C%E6%B1%82x%EF%BC%881-2%E9%99%A4%E4%BB%A51-x%EF%BC%89%E9%99%A4%E4%BB%A5%EF%BC%88x%2B1%EF%BC%89-x%EF%BC%88x%26%23178%3B-1%EF%BC%89%E9%99%A4%E4%BB%A5x%E5%B9%B3%E6%96%B9-2x%2B1%E7%9A%84%E5%80%BC)
已知x²+x-1=0,求x(1-2除以1-x)除以(x+1)-x(x²-1)除以x平方-2x+1的值
已知x²+x-1=0,求x(1-2除以1-x)除以(x+1)-x(x²-1)除以x平方-2x+1的值
已知x²+x-1=0,求x(1-2除以1-x)除以(x+1)-x(x²-1)除以x平方-2x+1的值
x²+x-1=0,则有:-x²=x-1
x[1-2/(1-x)]÷(x+1)-x(x²-1)/(x²-2x+1)
=x(x+1)/(x-1)(x+1) - x(x-1)(x+1)/(x-1)²
=x/(x-1) - x(x+1)/(x-1)
=-x²/(x-1)=1 .
x(1-2除以1-x)除以(x+1)-x(x²-1)除以x平方-2x+1
=x[(1-x-2)/(1-x)]/(x+1)-x(x+1)(x-1)/(x-1)²
=x/(x-1)-x(x+1)/(x-1)
=(x-x²+x)/(x-1)
=x²/(x-1)
=(1-x)/(x-1)
=-1
-1或-(2+根号5)