Certainly! Let's illustrate the differences between a function and a non-function using a table, a mapping diagram, and a graph.
Function: \( f(x) = 2x + 3 \)
1. Table Representation:
| \( x \) | \( f(x) \) | |---------|------------| | 1 | 5 | | 2 | 7 | | 3 | 9 | | 4 | 11 |
2. Mapping Diagram:
x f(x)
----------------
1 ----> 5
2 ----> 7
3 ----> 9
4 ----> 11
3. Graph Representation:
The graph of \( f(x) = 2x + 3 \) is a straight line with a slope of 2 and a y-intercept at \( (0, 3) \).
Non-Function: \( g(x) = \sqrt{x} \) with the mapping \( (x, y) \)
1. Table Representation:
| \( x \) | \( y \) | |---------|-----------| | 0 | 0 | | 1 | 1 | | 4 | 2 | | 4 | -2 | (This is the non-function aspect)
2. Mapping Diagram:
x y
----------------
0 ----> 0
1 ----> 1
4 ----> 2
|
----> -2 (This creates the non-function condition)
3. Graph Representation:
The graph of \( g(x) = \sqrt{x} \) is a curved line starting at the origin but since the square root function can produce multiple \( y \) values for a given \( x \) (like both 2 and -2 for \( 4 \)), it is represented as:
Summary:
- The first example, \( f(x) = 2x + 3 \), is a function because each input \( x \) corresponds to exactly one output \( f(x) \).
- The second example with \( g(x) \) involves two outputs (2 and -2) for the input \( 4 \), making it a non-function.