A rational number is a quotient of the form <math>\frac{a}{b}</math> where ''a'', ''b'' are [[integer]]s and ''b'' ≠ 0.
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A rational number is a quotient of the form <math>\frac{a}{b}</math> where ''a'', ''b'' are [[integer]]s and ''b'' ≠ 0. The set of rational numbers, usually denoted by <math>\mathbb{Q}</math> is an example of a [[totally disconnected set]] that is not [[locally compact]].