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If a = {1, 2, 3, 4} and B = {A, B, C, D}, Define Any Four Bijections from a to B. Also Give Their Inverse Functions. - Mathematics

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Question

If A = {1, 2, 3, 4} and B = {abcd}, define any four bijections from A to B. Also give their inverse functions.

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Solution

f1=(1, a), (2, b), (3, c), (4, d)⇒ f1={(a, 1), (b, 2), (c, 3), (d, 4)}

f2={(1, b), (2, a), (3, c), (4, d)f2{(b, 1), (a, 2), (c, 3), (d, 4)}

f3(1, a), (2, b), (4, c), (3, d)⇒ f31  {(a, 1), (b, 2), (c, 4), (d, 3)}

f{(1, b), (2, a), (4, c), (3, d)⇒ f4{(b, 1), (a, 2), (c, 4), (d, 3)}

Clearly, all these are bijections because they are one-one and onto.

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Chapter 2: Functions - Exercise 2.4 [Page 69]

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RD Sharma Mathematics [English] Class 12
Chapter 2 Functions
Exercise 2.4 | Q 22 | Page 69

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