Question 92072
simplify ( 2+3i ) ( 2 - 3i )
FOIL
{{{2(2)+2(-3i)+3i(2)+3i(-3i)}}}
{{{4-6i+6i-9i^2}}}
{{{4-9i^2}}}  i^2=-1
{{{4-9(-1)}}}
{{{4+9}}}
{{{highlight(13)}}}
Happy Calculating!!!