Question

WILL FAN AND MEDAL Multiply the following complex numbers:

(7 + 2i)(2 + 3i)

A. 8 + 25i
B. 20 - 25i
C. 20 + 25i
D. 8 - 25i

Answer 1

Well, let us FOIL.

Answer 2

First - Outer, Inner-Last.

Answer 3

Do you remember how to do that?

Answer 4

Well, first-inner.

Answer 5

7*2 + 2i*2.

Answer 6

We are multiplying the terms in the first number by the first term in the second number.

Answer 7

So then we do

Answer 8

+7*3i + 2i*3i.

Answer 9

im pretty sure its A, but im not positive

Answer 10

That is an easy method.

Answer 11

But foiling, I just realized, is a bit different.

Answer 12

You multiply the first by the first in the other, and the second by the second in the other, and the first by the last in the other, and the last by the first in the other.

Answer 13

http://en.wikipedia.org/wiki/FOIL_method

Answer 14

Both methods work.

Answer 15

A is correct.

Answer 16

Good job! Please give me a medal if I helped! :)

Answer 17

Have a nice day!

Answer 18

aight thank you