Question:
Let $A=\{1,2,3,4\}$ and $f=\{(1,4),(2,1)(3,3),(4,2)\} .$ Write down (f of).
Solution:
To find: $f$ o $f$
Formula used: $f$ o $f=f(f(x))$
Given: (i) $f=\{(1,4),(2,1)(3,3),(4,2)\}$
We have,
$f \circ f(1)=f(f(1))=f(4)=2$
$f \circ f(2)=f(f(2))=f(1)=4$
$f$ of $(3)=f(f(3))=f(3)=3$
$f \circ f(4)=f(f(4))=f(2)=1$
Ans) $f$ of $f=\{(1,2),(2,4),(3,3),(4,1)\}$