Let f: A → B be a function, and let {Bi: i ∈ I} be a...

Let f: A → B be a function, and let {Bi: i ∈ I} be a partition of B. Prove that {f−1(Bi): i ∈ I} is a partition of A. If ~_I is the equivalence relation corresponding to the partition of B, describe the equivalence relation corresponding to the partition of A. [REMARK: For any C ⊆ B, f−1C) = {x ∈ A: f(x) ∈ C}.]

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Colby Messinger answered 1 year ago

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