I'm working on a online mathematical learning environment. There is a mathematical editor where students can give their answers using a graphical interface:
However, we have had the problem in the past, that our online mathematical editor saw $xy$ as the variable $xy$ of length 2, instead of $x\cdot y$. This confused so many students that we now have an option that $xy$ is seen as $x\cdot y$.
However, now the question arises, what does $x2$ mean? We parse it know as the variable of $x2$ of length $2$.
If the solution of question is $2\cdot x$ and the student would give the answer as $x2$, would a teacher mark that as correct? I'm not sure, I guess it is very uncommon, but we do know from our analysis, that input like this is sometimes given in the editor.
My guess is that the student probably meant $x^2$ or maybe even $x+2$ and maybe mistyped the plus operator.
So my question is, what would be the correct way to parse this? Should we parse it as $x\cdot 2$ or as the variable $x2$?