What are all possible excel formulas?

Answer 1

There is a limited amount of functions, but there is no limit to the amount of formulas you can create, so that question is impossible to answer. It is like trying to answer "All possible sentences," which would also be impossible.

Answer 2

It is impossible to list all formulas here, because every formula you would do is different. It would be like asking someone to write all sentences that there are in the English language. There are a limited number of functions and types of calculations in a spreadsheet, in the same way that there are a limited amount of letters and words in the English language, but putting them together allows infinite possibilities. You use formulas to solve the problem that you are trying to solve, in the same way you put words together to say what you want to say. There is no limit, so you can't write them all here. See the related questions below for more information on formulas.