要分解表达式

1. 将光标置于表达式的末尾，插入符号求值运算符，然后在占位符中键入关键字 factor。

PTC Mathcad 将整数分解为质数的乘积。

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PTC Mathcad 将多项式或有理函数分解为低阶多项式或有理函数的乘积。

要进行更完全的分解，可在 factor 后键入逗号，然后键入一系列出现在表达式方根中的逗号分隔的根。

2. 键入诸如 x2 – 2 之类不能通过有理数分解的多项式 (因为其方根为无理数)。

PTC Mathcad 会原样返回多项式。

3. 要进一步分解多项式，可在关键字 factor 后键入其方根中的一个 √2。

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4. 要分解具有复根的多项式，可在 factor 后插入复数 i。

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5. 如果不知道多项式的方根，则可执行以下步骤：

a. 先使用关键字 solve 求解多项式。

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b. 复制出现在方根中根，或复制其中一个方根，然后粘贴至关键字 factor 后的占位符中。

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