Is there a fundamental mathematical function that requires 3 inputs or more? So a mathematical operation can be represented as a function that maps inputs to outputs. For example "sin(x)" is a function that maps 1 input to 1 output, and "a + b" maps 2 inputs to 1 output. My question is is there a function that requires a minimum of 3 inputs on a fundamental level? I'm not talking about something like "a + b + c" even though that has 3 inputs because the steps of solving that function are evaluated 2 variables at a time ie "(a + b) + c". Is there something that needs 3 or more inputs to make sense in the same way addition needs 2? I don't have very strong math background so I didn't know how to google my question properly or how to tag it here properly. Thank you for your patience.

Thanks for your answers and comments! A conditional statement is to me a satisfactory answer. In order for a conditional statement to make sense it requires (a) the condition, (b) the yield if the condition evaluates to true, and (c) the yield if the condition evaluates to false. To the best of my knowledge all three components are required. Sorry if this answer is not satisfactory to your interpretation of the question.
