Is it okay if math questions are ended with exclamation mark (!)?

Question

I don't know whether there is any rule about this. But I've been wondering that if a math question is ended with an exclamation mark, would it be misinterpreted with "factorial"? For example, consider this question below.

Calculate $6! \times 2!$

Does it mean that we should calculate $6! \times 2!$ or $6! \times 2$?
But now if we write the question as below:

Calculate $6! \times 2!!$

Does it mean that we should calculate $6! \times (2!)!$ or what?
Now if we write this instead:

Calculate $6! \times 2!.$

it's clearer that we must calculate $6! \times 2!$. But grammatically speaking, should an exclamation ended with an exclamation mark?

I know it's a kind of weird question, but what do you think?

Answer 1

There are no "official" rules for how you combine symbolic math expressions with the surrounding natural language, but you should obviously avoid ambiguity. Putting an exclamation mark right after a numeric expression where it could be interpreted as a factorial is likely to be confusing.

Also, conventional math writing (at least what I'm familiar with) is pretty dry and unemotional, so readers are more likely to interpret an ambiguous $!$ as a factorial than as an exclamation.

Answer 2

While writing on a blackboard, for an exclamation point "in English" I use a "bubble font", and/or often parentheses, as in chess notation: (!?) and (!) and (?) and so on...