# \left( adds space [duplicate]

Why $f\left(x\right)$ adds a space between f and the opening parenthesis while $f(x)$ does not? Is the space anyhow more correct typesetting for a function? If not, is there a way to remove the space added by \left( or prevent it from appearing?

This came as a huge surprise to me. Sorry if it is a duplicate, but I couldn't find anything similar.

Minimal working example:

\documentclass{article}
\usepackage[utf8]{inputenc}
\begin{document}
$f\left(x\right)$

$f(x)$
\end{document}


Sample output:

• \left adds a space by design (in most cases). Don't use it for function parentheses, it looks ugly – user31729 Mar 17 '18 at 22:31
• Why are you writing f\left(x\right) in the first place? – Mico Mar 17 '18 at 22:42
• Maybe I should delete the question now that I see the linked ones, but I still feel this is more specific. As a not-too-skilled user I thought the spacing had some meaningful reason and could be necessary for functions, too. – Rafael Mar 17 '18 at 22:58
• @Mico I was actually writing a command: \f{}, so I wanted the parentheses to be flexible. This was lost when writing the minimal example – Rafael Mar 17 '18 at 23:00