Question

Dose this tablet represent a function? Why or why not? {(2,1), (2,4), (3,4), (4,2), (5,5)}

Answer 1

Answer:

This mapping isn't a function.

Step-by-step explanation:

A mapping specifies a relation between two sets of items (input and output). For example, a mapping of the form $\lbrace (x_{0},\, y_{0}),\, (x_{1},\, y_{1})\rbrace$ would map the input $x_{0}$ to output $y_{0}$ and map the input $x_{1}$ to output $y_{1}$.

A function is a mapping where each input is associated with exactly one output.

Note that both $(2,\, 1)$ and $(2,\, 4)$ are in the mapping given in this question. The input $2$ is mapped to more than one outputs. Thus, this mapping isn't a function.