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下一个已解决问题最佳答案 - 由投票者2008-06-02 23:02:03选出
解:(x-1)(x-2)(x-3)(x-4)-24
=〔(x-1)(x-4)〕〔(x-2)(x-3)〕-24
=〔(x^2-5x+4)(x^2-5x+6)〕-24
=〔(x^2-5x)^2+10(x^2-5x)+24]-24
=(x^2-5x)^2+10(x^2-5x)
=(x^2-5x)[ x^2-5x+10]
=x(x-5)(x^2-5x+10)
其他回答(4)
-
(x-1)(x-2)(x-3)(x-4)+24
(x+1)(x+2)(x+3)(x+4)+1
=(x+1)(x+4)(x+2)(x+3)+1
=(x^+5x+4)(x^+5x+6)+1
另x^+5x=y,则原式变为
(y+4)(y+6)+1
=y^+10y+25
=(y+5)^
把x^+5x=y代入,得(x^+5x+5)^ -
(x-1)(x-2)(x-3)(x-4)-24
=(x∧2-3x+2)(x-3)(x-4)-24
=(x∧3-3x∧2+2x-3x∧2+9x-6)(x-4)-24
=(x∧3-6x∧2+11x-6)(x-4)-24
=(x∧4-6x∧3+11x∧2-6x-4x∧3+24x∧2-44x+24)-24
=x∧4-10x∧3+34x∧2-50x -
(x-1)(x-2)(x-3)(x-4)-24
=[(x-1)(x-4)][(x-2)(x-3)]-24
=[x^2-5x+4][x^2-5x+6]-24
=(x^2-5x)^2+10(x^2-5x)
=(x^2-5x)(x^2-5x+10)
=x(x-5)(x^2-5x+10) -
(x-1)(x-2)(x-3)(x-4)-24=[(x-1)(x-4)][(x-2)(x-3)]-24
=[(x^2-5x)+4][(x^2-5x)+6]-24
=(x^2-5x)^2+10(x^2-5x)+24-24
=x(x-5)(x^2-5x+10)


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