高中数学集合与常用逻辑用语简单的逻辑联结词_全称量词与存在量词.ppt

第三节　简单的逻辑联结词、全称量词与存在量词 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 1．命题p∧q，p∨q，綈p的真假判断 p q p∧q p∨q 綈p 真 真 ________ ______ ______ 真 假 ________ ________ _______ 假 真 ________ ________ _________ 假 假 ________ ________ _______ 真 真 假 假 真 假 假 真 真 假 假 真 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 2.量词 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 3．含有一个量词的命题的否定 命题 命题的否定 ?x∈M，p(x) _________________________ ?x0∈M，p(x0) ________________________ ?x0∈M，綈p(x0) ?x∈M，綈p(x) Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 1．命题“p∧q”与“p∨q”如何否定？ 【提示】　“p∧q”的否定是“綈p∨綈q”； “p∨q”的否定是“綈p∧綈q”． 2．全称(特称)命题的否定还是全称(特称)命题吗？其真假性与原命题有什么关系？ 【提示】　全称命题的否定是特称命题，其真假性与原命题相反； 特称命题的否定是全称命题，其真假性与原命题相反． Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 1．(人教A版教材习题改编)已知命题p：?x∈R，sin x≤1，则(　　) A．綈p：?x0∈R，sin x0≥1　　　 B．綈p：?x∈R，sin x≥1 C．綈p：?x0∈R，sin x0＞1 D．綈p：?x∈R，sin x＞1 【解析】　全称命题的否定是特称命题，“sin x≤1”的否定是“sin x＞1”，故选C. 【答案】　C Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evaluation only. Created with Aspose.Slides for .NET 3.5