Question

Explain in detail with at least two sentences how to represent the product of A and B geometrically given that A=15+56i and B = 7 + 4i. Give the coordinate of A • B in polar form.

Answer 1

Basically each part of the first complex number gets multiplied by each part of the second complex number. You are multiplying 2 binomials.

(15 + 56i(7 + 4i)

= 105 + 60i + 392i + 224i^2

= 105 + 452i - 224 ( because i^2 = -1)

= - 119 + 452i