The integrand is not handed down from on high.
被积函数并不是从天上掉下来的。
It is based on the properties about the path of integration and the integrand function.
根据积分路径和被积函数的特点，讨论了相应的计算复积分的方法。
The integral range and the integrand structure are the two key points of the function integral.
积分区域和被积函数结构是函数积分的两个关键点。
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