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RootSum

Usage

RootSum[f, form] 表示对所有满足多项式方程 f[x] Equal 0 x form[x]的和.


Notes

f 必须是诸如(#^5 - 2 # + 1)&的一个Function对象.
form 不必是一个多项式函数.
Normal[expr]RootSum对象展开为包含 Root对象的显式和.
fform 可以包含符号参数.
• 只要form是一个有理函数,RootSum[f, form]将自动进行化简.
RootSum 常在计算有理函数的积分时生成.
• 参见Mathematica 全书: 3.4.3节.
• 同时参见: Root.
Further Examples

This gives the sum of the seventh powers of the roots of the quintic.

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Here is the sum of the logarithms.

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The sum of exponentials is not evaluated explicitly, but we can get its numerical value with N.

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In this polynomial the coefficients of the linear term is symbolic. We can get numerical results by substitution.

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