[演示课件]“一元一次不等式”复习.ppt

第五章 复 习 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. 第1节 不等式的性质 1.不等式的概念： 把用不等号“”（或 “”，“?”，“?”）连接的式子叫作不等式。如： 12－5 99 2y＋５７　３０ －0.5 ０　　x＋y 25 2 x ?3 符号“?”读作“大于或等于”，也可读作“不小于”；等号“?”读作“小于或等于”，也可读作“不大于” 如： a ? 0表示a0或a=0 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、不等式的性质 (1)不等式的性质1，不等式的两边都加上（或都减去）同一个数或同一个代数式，不等号的方向不变. 即 如果ab，那么a+c b + c，且 a–c b – c (2) 不等式基本性质2：不等式的两边都乘以（或除以）同一个正数，不等号的方向不变. 即 如果ab，c0,那么ac b c， 且 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)不等式基本性质3：不等式的两边都乘以（或除以）同一个负数，不等号的方向改变. 即 如果ab，c0,那么ac b c， 且 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. 第2节 一元一次不等式的解法 1.基本概念 不等式的解：满足一个不等式的未知数的每一个值称为这个不等式的一个解. 不等式的解集：一个不等式的解的全体称为这个不等式的解集. 求一个不等式的解集的过程称为解不等式. 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.解一元一次不等式的方法 解一元一次不等式的方法与解一元一次方程的方法类似 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. Evalu