已知x*x-5x-2000=0,求((x-2)(x-2)(x-2)-(x-1)(x-1)+1)/x-2的值

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已知x*x-5x-2000=0,求((x-2)(x-2)(x-2)-(x-1)(x-1)+1)/x-2的值

已知x*x-5x-2000=0,求((x-2)(x-2)(x-2)-(x-1)(x-1)+1)/x-2的值
已知x*x-5x-2000=0,求((x-2)(x-2)(x-2)-(x-1)(x-1)+1)/x-2的值

已知x*x-5x-2000=0,求((x-2)(x-2)(x-2)-(x-1)(x-1)+1)/x-2的值
已知x*x-5x-2000=0,求((x-2)(x-2)(x-2)-(x-1)(x-1)+1)/x-2的值
2000=y*(y+5)=y^2+5y--->(y+2.5)^2=2000+25/4=8025/4-->y=sqrt(8025)/2-2.5
(x+y)(x-y-5)=0,so x=y+5 or x=-y
(x^2-4x+4)*(x-2)-(x^2-2x+1)+1=x^3-2x^2-4x^2+8x+4x-8-x^2+2x-1+1
=x^3-7x^2+14x
原始=x^2-7x+14-2=x^2-7x+12=x^2-5x-2x+12=2000-2x+12=2012-2x
when x=-y,原始=2012+2y
when x=y+5,原始=2012-2(y+5)=2002-2y
where y=sqrt(8025)/2-2.5
要是把题设((x-2)(x-2)(x-2)-(x-1)(x-1)-1)/x-2改成
((x-2)(x-2)(x-2)+(x-1)(x-1)-1)/x-2
那么结果就好了:
(x^2-4x+4)*(x-2)+(x^2-2x+1)-1=x^3-2x^2-4x^2+8x+4x-8+x^2-2x+1-1
=x^3-5x^2+10x
原始=x^2-5x+10-2=x^2-5x+8=2008