当x=根号3/3,求代数式(x^2-3x)/(x-2)-[x+3/(2-x)]的值

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当x=根号3/3,求代数式(x^2-3x)/(x-2)-[x+3/(2-x)]的值
当x=根号3/3,求代数式(x^2-3x)/(x-2)-[x+3/(2-x)]的值

当x=根号3/3,求代数式(x^2-3x)/(x-2)-[x+3/(2-x)]的值
(x^2-3x)/(x-2)-[x+3/(2-x)]
=(x^2-3x)/(x-2)+[-x+3/(x-2)]
=(x^2-3x)/(x-2)+[(-x^2+2x+3)/(x-2)]
=(x^2-3x-x^2+2x+3)/(x-2)
=(-x+3)/(x-2)
将x=√3/3代入
原式=(-√3/3+3)/(√3/3-2)
=-(17+√3)/11

原代数式=x(x-3)/(x-2)-[x-3/(x-2)]=-x+(x²-3x-3)/(x-2)=(-x²+2x+x²-3x+3)/(x-2)=(3-x)/(x-2)
将x=√3/3代入
原式=(3-√3/3)/(√3/3-6)=-(17+√3)/11

-(17+sqrt3)/11