# \leftroot

Used inside a \root...\of expression to shift the root index leftward relative to the radical.

https://texform.dev/latex/commands/leftroot

## Metadata

| Field | Value |
| --- | --- |
| Topic | [Fractions and roots](https://texform.dev/latex/topics/fractions-roots) |
| Packages | base |
| Allowed mode | math |
| Tags | presentation |
| Commonality | low |
| Kind | prefix |

## Syntax

### base

Argument specification: `m:I`

Used inside a \root...\of expression to shift the root index leftward relative to the radical.

## Examples

```latex
\root\leftroot{-3}3\of{x}
```

[Open in Playground](https://play.texform.dev/?input=%5Croot%5Cleftroot%7B-3%7D3%5Cof%7Bx%7D)

## Renderer support

| Package | MathJax | KaTeX | XeTeX |
| --- | --- | --- | --- |
| base | full | none | none |

## Usage frequency

<0.01% of formulas in the measured corpus contain this entry, rank 231 of 263 entries with frequency data.

## In TeXForm

TeXForm parses this entry as prefix syntax; the package determines its argument specification.

### [base/leftroot-drop](https://texform.dev/rules/base/leftroot-drop)

Drop the leftroot index-position hint in cleanup-oriented normalization.

Level: corpus. Fidelity: reading.

```latex
\leftroot{#1}
```

→

```latex

```

```latex
\sqrt[\leftroot{-2}3]{k}
```

→

```latex
\sqrt[3]{k}
```

## See also

- [\\uproot](https://texform.dev/latex/commands/uproot)

## Test cases

### base

| Input | Case | MathJax | KaTeX | XeTeX |
| --- | --- | --- | --- | --- |
| \sqrt[\leftroot{2} 3]{a} | Positive: ctx:in-root | Pass | Fail | Fail |