2x-6/x^2-4x+4除以12-4x/x^2+5X-6除以x^2+5x+6/x^2-5x-6

2x-6/x^2-4x+4除以12-4x/x^2+5X-6除以x^2+5x+6/x^2-5x-6
2x-6/x^2-4x+4除以12-4x/x^2+5X-6除以x^2+5x+6/x^2-5x-6

2x-6/x^2-4x+4除以12-4x/x^2+5X-6除以x^2+5x+6/x^2-5x-6
别忽略了分数线的作用,原来的分子分母分开写上下两行,输入电脑就要加括号啊
[ (2x - 6) / (x" - 4x + 4) ] / [ (12 - 4x) / (x" + 5x - 6) ] / [ (x" + 5x + 6) / (x" - 5x - 6) ]
= [(2x - 6) / (x" - 4x + 4)] X [(x" + 5x - 6) / (12 - 4x)] X [(x" - 5x - 6) / (x" + 5x + 6)]
= [ (2x - 6)(x" + 5x - 6)(x" - 5x - 6) ] / [ (x" - 4x + 4)(12 - 4x)(x" + 5x + 6) ]
= [ 2(x - 3)(x" + 6x - x - 6)(x" - 6x + x - 6) ] / [ 4(3 - x)(x" + 6x - x + 6)(x - 2)" ]
= [ 2(x - 3)(x + 6)(x - 1)(x - 6)(x + 1) ] / [ (-4)(x - 3)(x + 6)(x - 1)(x - 2)" ]
= [ (x - 6)(x + 1) ] / [ (-2)(x - 2)" ]
= [ x" - 5x - 6 ] / [ (-2)(x" - 4x + 4) ]
= [ x" - 5x - 6 ] / [ -2x" + 8x - 8 ]

2x-6/x^2-4x+4除以12-4x/x^2+5X-6除以x^2+5x+6/x^2-5x-6
=(2x-6/x^2-4x+4)* (x^2+5X-6/12-4x) *(x^2-5x-6/x^2+5x+6)
=(2(x-3)/(x-2)^2)* ((x-1)(x+6)/4(3-x)) *((x-6)(x+1)/(x+2)(x+3))
=(-1/(x-2)^2)* ((x...

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2x-6/x^2-4x+4除以12-4x/x^2+5X-6除以x^2+5x+6/x^2-5x-6
=(2x-6/x^2-4x+4)* (x^2+5X-6/12-4x) *(x^2-5x-6/x^2+5x+6)
=(2(x-3)/(x-2)^2)* ((x-1)(x+6)/4(3-x)) *((x-6)(x+1)/(x+2)(x+3))
=(-1/(x-2)^2)* ((x-1)(x+6)/2) *((x-6)(x+1)/(x+2)(x+3))
=-(x^2-1)(x^2-36)/[2(x-2)^2(x+2)(x+3)]
题目是否有误，计算结果不简便。

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