Question

Complex numbers, equations attached

Answer 1

1a)4-4i
1b)3-11i
1c)-10i-15
1d)-6-13i+21

Answer 2

e)
\[\frac{1}{5}+\frac{7}{5}i\]

Answer 3

you want method or answers?

Answer 4

lol! you posted your entire homework.. Can't you try some?

Answer 5

it isn't homework

Answer 6

and if I knew how to do this I wouldn't ask for help lol

Answer 7

so you want the methods too?

Answer 8

if you'd give them to me, yes

Answer 9

Finally!!!!!!!!!!!!!!!!!!!!!!! :D here r the answers for the rest of the problems

Answer 10

on 1h, what's the first part? i can't read it xD

Answer 11

\[\frac{-4+\sqrt{-20}}{2}=\frac{-4+\sqrt{20}i}{2}=\frac{-4+2\sqrt{5}i}{2}=-2+\sqrt{5}i\]

Answer 12

Thnx Satellite :D

Answer 13

yw

Answer 14

i think there is a mistake in the last one

Answer 15

thr is?

Answer 16

lets see

Answer 17

...

Answer 18

\[7\sqrt{-2}(-4\sqrt{-3})\]
\[7\sqrt{2}i\times (-4\sqrt{3}i)\]
\[-28\sqrt{6}i^2\]
\[28\sqrt{6}\]

Answer 19

is it wrong just to multiply -2 and -3 as usually?

Answer 20

i think mistake may have been writing
\[\sqrt{-2}\times \sqrt{-3}=\sqrt{6}\] it is only true that
\[\sqrt{a}\sqrt{b}=\sqrt{ab}\] if both
\[a,b>0\]

Answer 21

yes, that is the mistake. you can only multiply like that for positive numbers. it doesn't work for negative ones. although i have seen textbooks that just write is without the restriction

Answer 22

really????????????????????? I didn't know tht :$:$ Thnx for not telling me that :D :D thnx :D

Answer 23

so for example
\[\sqrt{-16}=4i\] and
\[\sqrt{-9}=3i\] right? so
\[\sqrt{-16}\sqrt{-9}=12i^2=-12\]
NOT
\[\sqrt{-16}\sqrt{-9}=\sqrt{144}=12\]

Answer 24

Got it... Thanks a looot :D :D

Answer 25

yw!