Answer:
1. Constant function(fixed function)
a function A=>B is determined by the formula f(x) is called a constant function if for every member of the domain the function always applies f(x)= C, where C is a constant number
2. Constant identity
a function f(x)is called an identitu function if each member of the function domain applies f(x) = x or each member of the domain function is mapped to itself.
