大家在小学阶段就知道“分母不能为O”这一特殊性质,但在初中学习分式的过程中,不少同学未注意到题目中这一隐含条件而导致解题失败.本文列举几例以引起同学们的重视.例1(武昌初二期末考试题)以下结论正确的有——(填序号).(1)1/x-2可变形为x/((x~2)-2x));(2)x/(x~2-2x)变形为1/(x-2);(3)使x/(x~2-2x)无意义的x值是x=0且x=2;(4)无论a、b为何值,代数式(a+2b)/(a-b)+ Everyone knows that the “denominator can not be O” is a special character in elementary school, but many students failed to notice the implicit condition of the subject in the process of learning the fraction in junior high school, which caused the problem to fail. A few cases to arouse the attention of the students.Example 1 (Wuchang early two exam questions) The following conclusions are correct - (fill in). (1) 1 / x-2 can be transformed into x / ((x ~ 2) -2x); (2) x / (x ~ 2-2x) deforms into 1 / (x-2); (3) x does not make sense for x / x = 2; (4) Algebraic formula (a + 2b) / (ab) + no matter what a, b is