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二重积分2

2023-07-02 12:20 作者:编程会一点建模不太懂  | 我要投稿

题目选自2016年考研数学一

已知平面区域

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计算二重积分

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题目给定的积分区域是由圆心在原点半径为2的圆的右半部分,和心形线在坐标平面右半部分构成的

虚线包围部分就是积分区域

题目中给出的积分区域是极坐标形式,所以本题采用极坐标计算

I%3D%5Ciint%5Climits_D%7Bxdxdy%7D

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题目分析:本题给出的积分区域是极坐标形式,明确了积分需要用极坐标法。其中难点在于熟悉常见的极坐标曲线绘图及其直角坐标转换。在计算积分过程中,对于高次的二项式展开、华里士公式等要非常熟悉。大题考察的是知识运用的综合性,包括在跨章节的知识面上以及计算过程中的小知识点,甚至包括了中学数学的部分知识点。

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