How to tell the difference between onto and one to one functions

The video tutorial explains the concept of functions, focusing on the definition and examples of functions, non-functions, one-to-one functions, and onto functions. It highlights the importance of each element in the domain mapping to a unique element in the range for a function to be valid. The tutorial also distinguishes between one-to-one and onto functions, providing examples and non-examples to clarify these concepts. Finally, it discusses the characteristics of functions that are both one-to-one and onto.

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