Let A = {a, b, c, d} and f : A → A be given by
Question:

Let $A=\{a, b, c, d\}$ and $f: A \rightarrow A$ be given by $f=\{(a, b),(b, d),(c, a),(d, c)\}$. Write $f^{-1}$.     [NCERT EXEMPLAR]

Solution:

We have,

$A=\{a, b, c, d\}$ and $f: A \rightarrow A$ be given by $f=\{(a, b),(b, d),(c, a),(d, c)\}$

Since, the elements of a function when interchanged gives inverse function.

So, $f^{-1}=\{(b, a),(d, b),(a, c),(c, d)\}$