Question:
Let $A=\{-2,-1,0,2\}$ and $f: A \rightarrow Z: f(x)=x^{2}-2 x-3 .$ Find $f(A)$
Solution:
Given :
$A=\{-2,-1,0,2\}$
$f: A \rightarrow Z: f(x)=x^{2}-2 x-3$
Finding f(x) for each value of x,
$f(-2)=(-2)^{2}-2(-2)-3=4+4-3=5$
$f(-1)=(-1)^{2}-2(-1)-3=1+2-3=0$
$f(0)=(0)^{2}-2(0)-3=0+0-3=-3$
$f(2)=(2)^{2}-2(2)-3=4-4-3=-3$
f in ordered pair is represented as
$f=\{(-2,5),(-1,0),(0,-3),(2,-3)\}$