Question

What is an expression that describes the relationship between each input and output

Answer 1

A function is a mathematical expression that describes the relation between each input and output . for example F(x) = x+2 In this equation F(x) is your output and x is your input .
If x=2 ; F(x) = 4 , If x= 3 ; F(x) = 5 .

Answer 2

mathematical relationship in which each input corresponds to the same terms.