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罗增儒先生在文[1]中讨论了这样一个问题,其教育意义值得我们思考.题目已知不等式2x~2-9x+a<0 ①有解,且每一个满足条件①的x至少满足下述两式之一:x~2-4x+3<0, ②x~2-6x+8<0, ③求a的取值范围.文[1]分析了两种结果完全不同的解答,罗先生认为,其中一种解法是错误的,它属于逻辑性错误,将充分而不必要条件误认为充要条件.罗先生的观点是正确的,但笔者总觉得其分析有些隐晦和复杂,有必
Mr. Luo Zengru discusses such a problem in [1], and its educational significance is worth our consideration. The topic known inequality 2x~2-9x+a<0 1 has a solution, and each x satisfying condition 1 satisfies at least the following One of the two equations: x~2-4x+3<0, 2x~2-6x+8<0, 3 finds the range of a. The paper [1] analyzes the two solutions with completely different results. Mr. Luo believes that One of the solutions is wrong. It is a logical error and mistakes the sufficient and unnecessary conditions as necessary and sufficient conditions. Mr. Luo’s point of view is correct, but the author always feels that his analysis is somewhat vague and complex.