The order of terms matters even when they commute

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Revision as of 08:41, 15 July 2021 by ColinBeveridge (talk | contribs) (The order of factors in a term follows apparently arbitrary conventions.)
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When writing a term that consists of several factors, the conventions regarding their order appear arbitrary. It is usual to write:

  • $xy$ and $yx$ in either order;
  • $5t$ but not $t5$ (to avoid confusion with $t_5$ or $t^5$);
  • $x\sqrt{2}$ but not $\sqrt{2}x$ (to avoid confusion with $\sqrt{2x}$).
  • $\sqrt{2}\sin x$ but not $\sin x \sqrt{2}$ (to avoid confusion with $\sin \left(\sqrt{2}x\right)$).