Is f(x) = 2x Onto, One-to-One, or a Bijection for Different Domains?

AI Thread Summary
The discussion focuses on understanding the concepts of onto, one-to-one, and bijection functions using the example f(x) = 2x across different domains: integers (Z), naturals (N), and reals (R). The user seeks clarification on whether f(x) is onto, one-to-one, or a bijection for these specific sets. It is emphasized that grasping the definitions of these types of functions is crucial to solving the problem. The importance of applying these definitions to the given function and domains is highlighted as a way to deepen understanding. Overall, the thread aims to clarify these fundamental concepts in function analysis.
raross
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Hey if anyone could help me with this I would be sooo grateful. I am trying to grasp the idea of onto, one-to-one and bijection(both) functions.

A sample problem is: If f(x) = 2x . What is f(Z), all integers. What is f(N), all naturals. What is f(R), all real. These are 3 different problems, and I am trying to figure out if they are onto, and/or one-to-one or bijection(which means both).

Any help would be a BIG HELP! Thanks!
 
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anyone?

anyone? Thanks
 
... =/
 
What is it you don't understand about one-to-one and onto functions?
 
Yeah, definitions are always the most important thing here. Type them up here and think about them for a bit and then we'll see what you're having trouble with.
 
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