Hey guys,

Today I came across a question about the function \(f(x)\), which takes the value \(x\) when \(x \in Q\) and the value \(1-x\) when \(x \notin Q\). Is this function continuous at any point?

I thought that \(f(x)\) would be continuous at \(x=0.5\) since the left and right hand limits seem to approach \(0.5\) near \(x=0.5\).

Am I correct? If so, why? If not, why?

Thanks!

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TopNewestDo you know what is the delta epsilon definition of a limit? – Calvin Lin Staff · 1 year, 4 months ago

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– Raj Magesh · 1 year, 4 months ago

Thanks a lot! I went through the wiki and worked out the answer to my question. The epsilon-delta definition is broader than the one I learnt in school...Log in to reply

hi – Lucy Oakley · 11 months ago

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– Raj Magesh · 11 months ago

Hey.Log in to reply

– Lucy Oakley · 10 months, 4 weeks ago

How are youLog in to reply

– Raj Magesh · 10 months, 4 weeks ago

Great, you?Log in to reply

These are called drichlet functions and these are continuos when both equations are equal – Harshita Arya · 1 year, 4 months ago

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