Final answer:
An injective function, or a one-to-one function, is a function where each element in the domain is mapped to a unique element in the range.
Step-by-step explanation:
An injective function, also known as a one-to-one function, is a function where each element in the domain is mapped to a unique element in the range. If a function is injective, it means that no two different elements in the domain are mapped to the same element in the range.
To determine if a function is injective, we need to check if different elements in the domain are mapped to the same element in the range. If there are no such cases, then the function is injective.
Without the information about the functions g and f, it is not possible to determine whether they are injective or not. The injectivity of a function depends on its specific definition and behavior.