The question asks how to write equations
, so this is not an answer in that sense. Here, I suggest a method on how to draw
them.
Since +
is an operation of coalescence, in general, and =
indicates identity (such that C
is A
and B
combined together), and since everything algebraic can be represented visually, the TikZ solution
is presented by:
MWE
\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{automata,positioning}
\begin{document}
\begin{tikzpicture}[%
>=stealth,
node distance=1.6cm,
on grid,
auto
]
\node[state] (A) [align=center,fill=blue!5]{{\large\textit{A}}};
\node (A1) [align=center,pos=0.25,left = of A,fill=green!15]{Raindrop\textit{\textsubscript{s\textsubscript{1}}}};
\node (S1) [below = of A]{};
\node[state] (B) [align=center,fill=blue!5,below=of S1]{{\large\textit{B}}};
\node (B1) [align=center,left = of B,fill=green!15]{Raindrop\textit{\textsubscript{s\textsubscript{2}}}};
\node[state,double] (C) [align=center,fill=blue!5,right=of S1,minimum size=3.8em]{{\large\textit{AB}}};
\node (C1) [align=center,right = of C,fill=green!15]{Raindrop\textit{\textsubscript{B\textsubscript{1}}}};
\draw[->] (A) edge (C);
\draw[->] (B) edge (C);
\end{tikzpicture}
\end{document}
which may be easier for some to grasp, since mixing two styles (algebra and plain language) adds a cognitive load for the reader since they have to untangle the two and then compare how their meanings intertwine.
It becomes immediately apparent upon inspection that the AB combination, C
, has properties different to its constituents (e.g., evenness), implying that the identity (=
) is only a partial description. A transformation has also occurred, with the creation of a new entity.
The letters can be upright or italic, as one pleases.
\text{A}_{\text{something}}
is wrong; the similar and correct thing would be\mathrm{A}_{\text{something}}
(A
is not text but a variable, if you want it to be upright then\mathrm
is the way to go).