Algebra-2

Question Analysis
The question tests the understanding of the definition of a function using a mapping diagram. A relation is a function if each input value (element in the domain) points to only one output value (element in the range).

Key Concept Explanation
A function requires that each input value in the domain corresponds to only one output value in the range. Multiple inputs can share the same output, but no input can correspond to more than one output.

Step-by-step Solution
1. List the given inputs and their corresponding outputs: 1 → 5, ...