Definition
165
[23M]Let \(A\) be a set and \(\sim \) an equivalence relation. We denote by
\[ \frac A\sim \]
the quotient space, that is, the set of all equivalence classes; the canonical projection is the map \(\pi :A\to \frac A\sim \) that associates each \(x\in A\) with the class \([x]\in A/\sim \).
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