所谓存在性问题是相对于中学数学课本中有明确结论的封闭型问题而言的.这类试题的知识覆盖面较大,综合性较强,灵活选择方法的要求较高,再加上题意新颖、构思精巧,具有相当的深度和难度.它重在考查学生的分析、探索能力和思维的发散性.存在性问题的特点是试题中的结论没有明确设 The so-called existence problem is relative to closed questions in the middle school mathematics textbooks that have definite conclusions. The knowledge coverage of such questions is relatively large, the comprehensiveness is strong, the requirements for flexible selection methods are high, and the questions are novel. The concept is sophisticated, with considerable depth and difficulty. It focuses on the analysis of students’ analysis, exploration capabilities and the divergence of thinking. The problem of existence problems is that the conclusions in the questions are not clearly defined.