Question

Find the product of these complex numbers.

(5+6i)(3-3i) =
A. 33 + 3i
B. 15 + 18i
C. 15 - 18i
D. -3 + 3i

Answer 1

A) 33+3i

Explanation:

Use the FOIL method: (a+b)(c+d)=ac+ad+bc+bd(a+b)(c+d)=ac+ad+bc+bd.

15−15i+18i+18

combine like terms

(15+18)+(−15i+18i)

simplify

33+3i