Question

Explain these to me so I don't get the same type question wrong again!!! Complex Numbers! MEDAL!!

Answer 1

@GABI_J

Answer 2

(−3 + 2i) • (2 + i)

Answer 3

What do you mean??

Answer 4

FOIL METHOD.

Answer 5

http://www.mathwords.com/f/foil_method.htm

Answer 6

if i explain 9/10 chances i wont get a medal :'c

Answer 7

Yes, Foil.
\[(a+b)(c+d)\]
\[ac+ad+bd+bc\]

Answer 8

Okay let me try one sec!

Answer 9

\[(−3 + 2i) • (2 + i)\]
Recalling)

Answer 10

Oh gawsh i still probably got it wrong as I suck at math but I got -8-i

Answer 11

Almost, look over your work again!

Answer 12

One part is wrong the other is right?
Which one is wrong -8 or
-i
what do you think?

Answer 13

-8+i??

Answer 14

I did wrong signs

Answer 15

Yes,

Answer 16

you are right now

Answer 17

Okay one more! And thanks so much!!

Answer 18

Ask away!

Answer 19

(1 + 2i) • (5 − 3i)

Answer 20

let me try... :)

Answer 21

you can do it!

Answer 22

11+7i?

Answer 23

Yes!

Answer 24

Can I give you a harder example?

Answer 25

Ahh thanks so much! Your a life saver!!

Answer 26

and sure!

Answer 27

OK, ready?

\[\frac{5+i}{2-i}\]

This is also trig, but a little harder
Hint to think_ you can have a radical in a denominator

Any ideas?

Answer 28

hmmm give me a hint!

Answer 29

Multiply the equation by \[\frac{2+i}{2+i}\].

this is what I refer to as a magical 1.

Answer 30

I'll right it out for you, and you multiply, Ok?

Answer 31

always? OK

Answer 32

\[\frac{(5+i)(2+i)}{(2-i)(2+i)}\]

Right? Do this one for me real quick.

Answer 33

What do you do with the I's? Sqaure them? But if you square them arent they just like a -1?

Answer 34

i^2 is exactly -1

Answer 35

So write it out for me please....

Answer 36

Okay! So I am ushally wrong but....\[\frac{ 10-1 }{ 4-1 }=\frac{ 9 }{ 3 }= 3\]

Answer 37

No, ain't right!

Answer 38

You forgot about the middle term on top!

Answer 39

\[(5+i)(2+i)\] what is the middle term?

Answer 40

Im lost!! I try re-doing it and I got something like this :(\[\frac{ 9+10i }{ 3+0 }\]

Answer 41

Nope!

Answer 42

9 is right, what is wrong?

Answer 43

You got confused it is not 2*5i
it is 2i+5i
Don't you see that?

Answer 44

\[(a+b)(c+d)_\]
\[a(c+d)+b(c+d)_\]
\[ac+ad+bc+bd_\]

Answer 45

wait so just 10 lmao?

Answer 46

No, it is 9+7i

b/c the number of i s is 2+5
see (I mean if you foil, step by step)

Answer 47

geeez I'm terrible at math xD

Answer 48

Do you understand?

Answer 49

\[Understand?\]

Answer 50

kind of sort of!