(x-1)/(x-3)＞0解法一,a,x-3＞0,且x-1＞0,则：x＞3b,x-3＜0,且x-1＜0,则：x＜1解法二,(x-1)/(x-3)＞0的解和(x-1)·(x-3)＞0的解相同!解(x-1)·(x-3)＞0方法1：a,x-3＞0,且x-1＞0,则：x＞3b,x-3＜0,且x-1＜0,则：x＜1...分式为什么 换成(x-1)·(x-3)＞0(x-1)/(x-3)＞0的和(x-1)·(x-3)＞0不是一回事，但是两者有同解！