# finverse

Functional inverse

## Syntax

``g = finverse(f)``
``g = finverse(f,var)``

## Description

````g = finverse(f)` returns the inverse of function `f`, such that `f(g(x)) = x`. If `f` contains more than one variable, use the next syntax to specify the independent variable.```

example

````g = finverse(f,var)` uses the symbolic variable `var` as the independent variable, such that `f(g(var)) = var`.```

## Examples

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Compute functional inverse for this trigonometric function.

```syms x f(x) = 1/tan(x); g = finverse(f)```
```g(x) = atan(1/x)```

Compute functional inverse for this exponential function by specifying the independent variable.

```syms u v finverse(exp(u-2*v), u)```
```ans = 2*v + log(u)```

## Input Arguments

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Input, specified as a symbolic expression or function.

Independent variable, specified as a symbolic variable.

## Limitations

• `finverse` does not issue a warning when the functional inverse is not unique.

## Version History

Introduced before R2006a