Question

Simplify the given expression.

(7 − 3i) • (2 − i)

4 + i

14 + 3i

11 − 13i

14 − 10i

Answer 1

So...
We distribute so that...

7 * 2 = 14
7 * i = 7i

then

-3i * 2 = -6i
-3i * -i = 3i?

Answer 2

then combine like terms...

7i - 6i + 3i = 4i

so 14 + 4i?

Answer 3

dang that isn't a possible answer :S

Answer 4

You MUST recall that
\[\Large i^2 = -1\]

Answer 5

wait a minute!

-3i * i = 3i^2 right?

Answer 6

right

Answer 7

7i - 6i + 3i^2...

1i + 3i^2 is idk...

Answer 8

and i^2 = -1, so you have 3(-1)-13i+14 = -3-13i+14=11-13i

Answer 9

3(-1)

-3 so 1 -3
-2?

Answer 10

lol I can't get this xD

Answer 11

you're getting your negative numbers wrong.....-7 times i is -7i

Answer 12

hmm...

7 * 2 = 14
7 * i = 7i

then
-3i * 2 = -6i
-3i * -i = 3i^2

3i^2 is 3(-1) so -3...

14 - 3

11

then 7i - 6 = 1i or i

Answer 13

>.<

Answer 14

ohhhhh

Answer 15

7 * -i
= -7i

Answer 16

11 - 13i?

Answer 17

did i get it :D?

Answer 18

FOIL First, inside, outside, last
(7)(2)=14
(-3i)(2)=-6i
(7)(-i)=-7i
(-3i)(-i)=3i^2
Combine like terms
3i^2-13i+14
i^2 in imaginary numbers=-1
3(-1)-13i+14=-13i+11 or 11-13i

Answer 19

you got it!

Answer 20

Thanks for the help man

Answer 21

You're welcome!