3.6.5 Converting Power Series to Normal Expressions
| Normal[expr] | convert a power series to a normal expression |
Converting power series to normal expressions. As discussed above, power series in Mathematica are represented in a special internal form, which keeps track of such attributes as their expansion order. For some purposes, you may want to convert power series to normal expressions. From a mathematical point of view, this corresponds to truncating the power series, and assuming that all higher-order terms are zero. | This generates a power series, with four terms. | |
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t = Series[ ArcTan[x], {x, 0, 8} ]
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| Squaring the power series gives you another power series, with the appropriate number of terms. | |
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| Normal truncates the power series, giving a normal expression. | |
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| You can now apply standard algebraic operations. | |
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| SeriesCoefficient[series, n] | give the coefficient of the   order term in a power series |
Extracting coefficients of terms in power series. This gives the coefficient of  in the original power series. | |
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SeriesCoefficient[t, 7]
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