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...