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Question
If A = {a, b, c, d} and f = {a, b), (b, d), (c, a), (d, c)}, show that f is one-one from A onto A. Find f–1
Solution
f is one-one since each element of A is assigned to distinct element of the set A.
Also, f is onto since f(A) = A.
Moreover, f–1 = {(b, a), (d, b), (a, c), (c, d)}
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