the function f(x) = 1 if x is rational(adsbygoogle = window.adsbygoogle || []).push({});

f(x) = 0 if x is irrational is not continuous for all real numbers, c

the function f(x) = x if x is rational

f(x) = 0 if x is irrationa is continuous at x=0 and not continuous for all other real numbers c

the function f(x) = 1/q if x is rational and x = p/q in lowest terms

f(x) = 0 if x is irrational

is continuous at c if c is irrational and not continuous at c if c is rational

I'm terrible at proofs, please help!

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# Function proofs

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