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Function

Definition A function/: X —>Y is an assignment (a

rule)f

such tliat

Vx ex 3\y i=Yy=f(x).

X is called the domain and Y the codomain of/.

The element x is called the argument (input, independent

variable) and y is the value of the function/(output, dependent variable).

The set of all possible values is called the rangę of the function/:

Rf= (y : 3x(EXy =f(x)}. Rf o Y