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

F(x) = x if x is rational, 0 if x is irrational.

Use the δ, ε definition of the limit to prove that lim(x→0)f(x)=0.

Use the δ, ε definition of the limit to prove that lim(x→a)f(x) does not exist for any a≠0.

2. Relevant equations

lim(x→a)f(x)=L

0<|x-a|<δ, |f(x)-L|<ε

3. The attempt at a solution

I was mostly having troubles writing my initial equation, I was stumped very early on by filling in the values for the epsilon part of the equation, if that's how one is supposed to go by this problem. If not, any other advice that can be given to me?

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# F(x) = x if x is rational, 0 if x is irrational.

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