Example A function ’ f ’ is defined on the set of integers as

1) Find the domain of ’ f ’

2) Find the range of ’ f ’

3) Find f (4 )

4) State whether f is a one-one or many one function.

1) The domain of f = { 1, 2, 3, 4, 5 }

2) The range of f = { 2, 3, 5 }

3) 4 belongs to the interval ( 4, 6 )

4) It is a many - one function

Example A = {-2, -1, 1, 2 }and f ( x ) = { ( x,  ) : x Î A }

1) List the domain of f

2) List the range of f

3) Is f a function ?

Solution :

1) The domain of ’ f ’ is the set A = { -2, -1, 1, 2 }

3) Yes, it is a function.