Algebra 8
2 marks · NormalWrite down, giving a reason, whether the following mapping represents a function.
| x | y |
|---|---|
| −2 | 4 |
| 1 | 3 |
| 3 | 5 |
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
Yes, it is a function. Each input maps to exactly one output.
Also accept: Yes, since each input has only one output assigned.
Common mistakes: Saying it is not a function because different outputs occur.; Not referencing the 'exactly one output' definition.
Show mark scheme and worked solution
Marking points
M1 · 1 mark · States correct decision: is a function.
A1 · 1 mark · Gives valid supporting reason: Each input has only one output.
Worked solution
Each value of x (−2, 1, 3) is linked to only one value of y. So, this mapping is a function because every input has exactly one output.