Question

Simplify the given expression:

(−5 + 3i) • (1 − 2i)

Answer 1

This is like the other one. Use foil first.

Answer 2

okay -5 * 1
-5*-2i
3i*1
3i*-2i

Answer 3

FOIL means first, inner, outer, last.

Answer 4

thats what i did .

Answer 5

-5 * 1
3i * 1
-5 * -2i
3i * -2i

Answer 6

okayy now what is the next step

Answer 7

Tell me what you have after multiplying all of those.

Answer 8

-5 * 1=-5
3i * 1=3i
-5 * -2i =10i
3i * -2i= -6i

Answer 9

When you multiply 3i and -2i you get -6i^2.

Answer 10

So you have -5 + 3i + 10i - 6i^2
Remember what i^2 is.

Answer 11

-1

Answer 12

So
-5 + 3i + 10i - 6(-1)

Answer 13

now ?

Answer 14

Now... solve it.

Answer 15

Combine like terms.

Answer 16

-30 + 10i Im guessing

Answer 17

ughhh im pretty sure thats wrong because these are my choices
−5 − 6i

1 + 13i

2 + i

4 − 5i

Answer 18

+ 13 I Meant

Answer 19

-5 + 3i + 10i - 6(-1)
Okay, well you're doing it wrong. What is:
-6 * -1

Answer 20

= 6

Answer 21

Right, so
-5 + 3i + 10i - 6(-1)
-5 + 3i + 10i + 6

Answer 22

Combine like terms.

Answer 23

13i +1

Answer 24

1 + 13i. It's better like that. :D

Answer 25

okayy now i got it im just not sure how 1^2 Comes Into Play

Answer 26

You're not sure how i^2 = -1?

Answer 27

no why 1^2 is put in to the equation

Answer 28

You mean you don't know why i * i = i^2?

Answer 29

like is it always going to be 1^2

Answer 30

I don't understand, there is no 1^2 in there.

Answer 31

brb

Answer 32

you asked in the beginning what is 1^2 Right I Said -1 So The You Put It In The Equation -5 + 3i + 10i - 6(-1) <------ why

Answer 33

1^2 is 1. I said i as in the letter i.

Answer 34

i^2 = -1
Don't question why, because it's confusing and it won't ever help you in real life. Just accept it. :D

Answer 35

So 6i^2 is 6 * i^2 and i ^2 = -1 so you sub it in and then you have
6 * -1
6(-1)

Answer 36

Do you get it now?

Answer 37

yes

Answer 38

Okay, try simplifying this so I can make sure you understand it well.
(5 - 2i)(-5 + 4i)