I am not an native English speaker and I would like to know if the use of the word "vacuous" is offensive.
I am writing a reply to a request where I am asked to do something that has no sense at all in a mathematical context. Basically, I was requested to do some calculations on a mathematical object that is provably nonexistent. In my reply I want to be direct and say that trying to do so is useless. Then, I was planning to say that this is vacuous. I also want to be as polite as possible, then my hesitation on using this word. Any pointers to a more suitable word would also be appreciated.