三角函数定义域与值域L.ppt
文本预览下载声明
* Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 一.复习(3分钟完成) 1.在同一坐标系内,用五点法分别画出函数 y= sinx和 y= cosx, x?[0, 2?]的简图: y x o 1 -1 y=sinx,x?[0, 2?] ` y=cosx,x?[0, 2?] 2.写出y=sinx和y=cosx的定义域,值域,最值,周期 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 二.填表 定义域 值域 最值 周期 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 一. 求三角函定义域: 点拨:1.列出三角不等式 2.根据图象写出不等式的解集 例1.求下列函数的定义域; Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 二.求 三角函值域的几种典型形式 一)一次型 练习:口答下列函数的值域 (1)y=-2sinx+1 (2) y=3cosx+2 [-1,3] [-1,5] 总结:形如y=asinx+b的函数的最大值是 最小值是 直接代入法 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 二)二次型 0 y t 1 -1 点拨:1.换元(注明新元取值) 2.运用二次函数图象性质(一看对称轴,二看区间端点) 点拨:统一函数名 二次函数法 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 三) 分式型 点拨: 1.反表示 两边平方 反表示法 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 四)二合一 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 五) 其他形式: 0 y x Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 六:应用题求最值 A B C D Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. A B D C Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.
显示全部