Question

How do you simplify `(-3 - 2i)(-3 + 3i)`?

Answer 1

`15-3i`

Explanation:

#{: (xx," | ",-3,-2i), ("------",,"------","------"), (-3," | ",+9,+6i), (+3i," | ",-9i,-6i^2), (,"------","------","------"), (,9,-3i,-6i^2) :}#

Since `i^2=-1`
`rarr -6i^2= +6`

Therefore
`(-3-2i)(-3+3i)=9-3i-6i^2 = color(green)(15-3i)`