TeXipedia

xleftarrow

Creates an extensible left-pointing arrow that automatically adjusts its width to accommodate text above or below it.

Overview

Particularly valuable in mathematical expressions where arrows need to be labeled with explanatory text or mathematical notation.

  • Common in proof writing and mathematical reasoning to show implications or transformations.
  • Essential for diagram-like mathematical expressions where steps or relationships need clear labeling.
  • Often used in conjunction with equation alignments to demonstrate sequential mathematical operations.
  • Frequently appears in algebraic derivations, formal logic, and category theory where labeled transitions are important.

Examples

Showing a reaction mechanism with a labeled left arrow.

AheatB\text{A} \xleftarrow{\text{heat}} \text{B}
\text{A} \xleftarrow{\text{heat}} \text{B}

Indicating a reverse mapping between sets with a description.

YinverseXY \xleftarrow{\text{inverse}} X
Y \xleftarrow{\text{inverse}} X

Showing convergence of a sequence with a limit description.

xnnLx_n \xleftarrow{n \to \infty} L
x_n \xleftarrow{n \to \infty} L