Q. If $z = 2 - 3 i$ , then value of $z^{2} - 4 z + 13$ is

1165 265 Complex Numbers and Quadratic Equations Report Error

A

0

B

1

C

2

D

3

Solution:

We have, $z = 2 - 3 i$
$\Rightarrow z - 2 = - 3 i$
$\Rightarrow (z - 2)^{2} = (- 3 i)^{2}$
$\Rightarrow z^{2} - 4 z + 4 = 9 i^{2}$
$\Rightarrow z^{2} - 4 z + 13 = 0$