# Beta reduction

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Revision as of 16:49, 29 January 2007 by MathematicalOrchid (talk | contribs) (Improvements in wording?)

A *beta reduction* (also written *β reduction*) is basically where you actually apply a lambda function to an expression to generate a result.

For example, suppose we have

```
(\x y -> 2*x*x + y) 7
```

If we now replace every occurance of `x`

with 7, we arrive at

```
\y -> 2*7*7 + y
```

We have thus performed a *beta reduction*.