(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

i) Show explicitly that any non-injective function with a right inverse has another right inverse

ii) Give an example of a function which has (at least) two distinct left inverses

2. Relevant equations

i) I don't believe there are any.

ii) "

3. The attempt at a solution

i) Since it says "explicitly" I doubt that my attempt would count as a solution even if it were correct, but here it is;

Since the function is non-injective and has a right inverse, it must therefore be surjective as it cannot be bijective, and in order for this function to be surjective it must have at least one more right inverse.

I also tried showing first that f(x) = x^3 - x is non-injective and then showing that the values x = -1,0,1 map to f(x) = 0 that I would be showing this is true but I am not sure if it is correct.

ii) For this I am really not sure if there is an easier way to do it apart from trial and error but I understand the theory behind it.

Thanks in advance,

SD123

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# Surjective functions

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