Under the certain conditions, the average RCS of targets with complex shape are generally subject to the arithmetic sum of the mean RCS by local reflection area.

在一定的条件下，复杂形体的目标平均雷达截面积近似地由局部反射区域平均雷达截面积的算术和来确定。

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Instead they may involve, at most, a little arithmetic, such as "the sum of two odd numbers is even", and common sense.

相反，它们最多可能涉及一点算术，比如“两个奇数之和为偶数”，以及常识。

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We first introduce methods of finding the sum of the first n terms for an arithmetic sequence of higher order.

我们首先介绍了高阶等差数列前 n 项和的求解方法。

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In fact, there are some very old books that show this as the average, the sum divided by two arithmetic mean, but the modern practice is to use the geometric mean.

事实上，一些很老的书籍上,平均的定义就是算数意义的，总的来说被分为两种算数意义，但现代我们多用几何意义。

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