Question

PLEASE HELP ME!

Answer 1

Are you okay simplifying this to here?
\[\frac{7i}{1+9i}\]

Answer 2

*There's a little bit more after this, but I can walk through the steps for the first part if you want.

Answer 3

yeah, I juse dont really remember what to do after this.

Answer 4

Do you know what a conjugate is? Like if I asked you what the conjugate of 1+9i is.

Answer 5

1-9i

Answer 6

Right! So, math teachers are kind of picky about how they want you to represent your expressions. You're not "supposed to" have square roots in the denominators of fractions, and since i is the square root of -1, we are technically supposed to make sure there aren't any i's in the denominator either. The best way to get rid of them is to multiply by the conjugate.
\[\frac{7i}{1+9i} \frac{1-9i}{1-9i}\]

Answer 7

Multiply that and the i's in the denominator should drop out.

Answer 8

so 1 - 81 for the denom?

Answer 9

1+81

Answer 10

I was close... ahha -.-

Answer 11

I always mess up the signs

Answer 12

so the top is 7-63?

Answer 13

+ again. Sorry!

Answer 14

Oh, it's 7i also

Answer 15

I quit. -.- lmao ok

Answer 16

\[\frac{7i+63}{82}\]

Answer 17

THANKS! one more?

Answer 18

No worries. Sure :)

Answer 19

I have been doing math ALL day and this is the end!!! haha

Answer 20

Alright, be careful on this one. What do you have so far?

Answer 21

*Or, I guess, let me know if/when you get stuck

Answer 22

you distribute the 6 right? sorry my computer froze

Answer 23

First thing you should do is pull out the square root of negative 1 as i. Then yeah, you'll distribute after that.

Answer 24

-2sqrt6 + 4 sqrt 3? as the answer

Answer 25

@jabberwock

Answer 26

Close to what I got. Let me look it over again.

Answer 27

the sign? -.-

Answer 28

There should be an i on that 2sqrt6, I think. I also have the signs the other way around
\[2\sqrt{6}i-4\sqrt{3}\]

Answer 29

thats not a choice

Answer 30

What are the choices?