Question

Determnine if each table shown below represents a function or not.

Answer 1

                                                 Table 1

Input (x)               1            3           5            5              9

Output (y)             7           16          19          20           28

We know that a function is a relation where each input or x-value of the X set has a unique y-value or output of the Y set.

In other words, we can not have duplicated inputs as there should be only 1 output for each input.

From Table 1, it is clear that:

• Each input or x-value of the X set has a unique y-value or output of the Y set.

• There is no duplicated input (repeated x value).

Therefore, Table 1 represents a function.

                                                Table 2

Input (x)               0.5          7           7            12            15

Output (y)             7           15          10          23           30

 

We already know that a function is a relation where each input or x-value of the X set has a unique y-value or output of the Y set.

In other words, we can not have duplicated inputs as there should be only 1 output for each input.

From Table 2, it is clear that:

• There is a duplicated input (repeated x value) i.e. x = 7 appears twice. And we can not have repeated input values.

As the input x = 7 is repeated multiple times, thus, the given table 2 does not represent a function.

Therefore,  Table 2 does not represent a function.