2013高考数学(江苏专版)二轮专题课件：第二部分 专题3 转化与化归思想.ppt

返回 第二部分 专题3 小题基础练清 增分考点讲透 配套专题检测 备考方向锁定 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. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 化归就是转化和归结，它是解决数学问题的基本方法，在解决数学问题时，人们常常是将需要解决的问题，通过某种转化手段，归结为另一个相对较容易解决的或者已经有解决模式的问题，以求得问题的解答.中学数学处处都体现出化归的思想，如化繁为简、化难为易、化未知为已知，化高次为低次等，它是解决问题的一种最基本的思想. 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．f(x)是R上的奇函数，f(x＋2)＝f(x)，当0≤x≤1时，f(x)＝x， 则f(7.5)等于________． 解析：由f(x＋2)＝f(x)知，f(x)的周期为2，所以f(7.5)＝f(－0.5)＝－f(0.5)＝－0.5. 答案：－0.5 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. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 4．已知关于x的方程x2＋2alog2(x2＋2)＋a2－3＝0有惟一解，则 实数a的值为________． 解析：令f(x)＝x2＋2alog2(x2＋2)＋a2－3，显然f(x)是偶函数，方程f(x)＝0要有惟一实根，则此根必为x＝0，故2a＋a2－3＝0，解得a＝1或a＝－3，当a＝－3时，易知方程f(x)＝0不止有一个实根，故a＝1. 答案：1 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. 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. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2