CPM Homework Help : A2C Problem 12-11

Simplify.

$\left(2 + 3i\right)\left(2 − 3i\right) + \left(2 + 3i\right)^{2}$
Hint (a):
$4 − \left(−9\right) + 4 + 12i + \left(−9\right)$
Answer:
8 $+ 12i$

$\frac { 2 + 3 i } { 2 - 3 i }$
Hint (b):
$\frac{2+3i}{2-3i}\cdot\frac{2+3i}{2+3i}$
Answer (b):
$-\frac{5}{13}+\frac{12}{13}i$