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Set Theory, Relations, Functions: preliminaries: part 10: more tutorial problems for practice

Problem 1: Prove that a function f is 1-1 iff $latex f^{-1}(f(A))=A$ for all $latex A \subset X$. Given that $latex f: X \longrightarrow Y$. Problem 2: Prove that a function if is onto iff $latex f…