Question

Simplify the expression.
(–2 – 2i)(–4 + 6i)

>8 – 4i
>8 – 12i
>20 – 4i
>–4 – 4i

Answer 1

Do you know the value for i (iota) ?

Answer 2

just multiply everything and you should get the answer (i*i=-1)

Answer 3

\[\quad(–2 – 2i)(–4 + 6i) \]
\[=-2(–4 + 6i) -2i(-4+6i)\]

Answer 4

\[\large{(-2-2i)(-4+6i)}\]
\[\large{-2(-4) -2i(-4) -2(6i) -2i(6i)}\]
\[\large{8 + 8 i - 12 i -12i^2}\]

Answer 5

>–4 – 4i

Answer 6

Now since : \[\large{ i = \sqrt{-1} }\]

Therefore, \[\large{i^2 = (\sqrt{-1})^2 = -1 }\]

Answer 7

Solving this we get : 8 - 4i - 12 = -4-4i

Answer 8

Therefore the answer is : >-4-4i

Answer 9

thank you all so much, i've got it now! @SheldonEinstein @surdawi

Answer 10

Nice!

Answer 11

mistake !

Answer 12

20 -4i

Answer 13

Sorry it will be : \[\large{8 + 12 - 4i = 20 -4i}\]

Answer 14

I am REALLY VERY VERY SORRY for that... Thanks @UnkleRhaukus for pointing it out.

Answer 15

\[-12i^2=+12\]

Answer 16

Yeah