Chapter 13

Symbolic Calculation

Overview of Symbolic Math

Live Symbolic Evaluation

Using the Symbolics Menu

Examples of Symbolic Calculation

Overview of Symbolic Math

When you evaluate an expression numerically, Mathcad returns one or more numbers, as shown at the top of Figure 13-1. When Mathcad calculates symbolically, however, the result of evaluating an expression is generally another expression, as shown in the bottom of Figure 13-1.

Figure 13-1: A numeric and symbolic evaluation of the same expression. The symbolic transformation can yield insight into the underlying expression.

There are two ways to perform a symbolic transformation on an expression:

•You can use the symbolic equal sign with keywords.

•You can use commands from the Symbolics menu.

Online Help You can make the numeric and symbolic processors work together, so that an expression is simplified before the numeric processor calculates it. See “Symbolic Optimization” in online

Help.

Note For a computer, symbolic operations are, in general, much more difficult than the corresponding numeric operations. In fact, many complicated functions and deceptively simple-looking functions have no closed-forms as integrals or roots.

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