已知x的平方-2x=2,求(x-1)的平方+(x+3)(x-3)+(x-3)(x-1)得值

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已知x的平方-2x=2,求(x-1)的平方+(x+3)(x-3)+(x-3)(x-1)得值已知x的平方-2x=2,求(x-1)的平方+(x+3)(x-3)+(x-3)(x-1)得值已知x的平方-2x=

已知x的平方-2x=2,求(x-1)的平方+(x+3)(x-3)+(x-3)(x-1)得值
已知x的平方-2x=2,求(x-1)的平方+(x+3)(x-3)+(x-3)(x-1)得值

已知x的平方-2x=2,求(x-1)的平方+(x+3)(x-3)+(x-3)(x-1)得值
x²-2x=2
(x-1)²=3
(x-1)²+(x+3)(x-3)+(x-3)(x-1)
=3+x²-9+x²-4x+3
=2x²-4x-3
=2(x²-2x+1)-5
=2(x-1)²-5
=2*3-5
=1

(x-1)^2+(x+3)(x-3)+(x-3)(x-1)
=(x-1)^2+〔(x+3)+(x-1)〕(x-3)
=(x-1)^2+2(x+1)(x-3)
=x^2-2x+1+2x^2-4x-6
=3x^2-6x-5
=3(x^2-2x)-5
=3*2-5
=1


(x-1)的平方+(x+3)(x-3)+(x-3)(x-1)
=x^2-2x+1+x^2-9+x^2-4x+3
=3x^2-6x-5
=3(x^2-2x)-5
x的平方-2x=2
=6-5
=1