Prove Riemann Integrability of Function f on [0,1]

[math2006]

Given a function $$f: [0,1] \to \mathbb{R}$$. Suppose $$f(x) = 0$$ if x is irrational and f(x) = 1/q if x = p/q, where p and q are relatively prime.
Prove that f is Riemann integrable.

 

[quantumdude]

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