每个定理或公式都有它成立的条件和适用范围,因此,解决数学问题要注意问题的条件,忽视问题条件是解题出现错误的重要原因之一, 现就这类问题分类举例如下. Each theorem or formula has its established conditions and scope of application. Therefore, the solution to mathematics problems should pay attention to the conditions of the problem. Ignoring problem conditions is one of the important reasons for the error in solving problems. The classification of such problems is given as follows.