Question

What is 4 + (-4i^2)

Answer 1

A complex number

Answer 2

Is i an imaginary unit or a variable?

Answer 3

I don't know is just from online math test me was doing.

Answer 4

\(i^2 = -1\)

Answer 5

What are the options you are given?

Answer 6

(a) 8 (b) 4 (c) -8 (d) 0

Answer 7

Just plug in i^2=-1 and solve .

Answer 8

The imaginary number i is defined solely by the property that its square is −1

Answer 9

4 + (-4i^2)=4+(-4(-1)=..

Remember

(a)(-b)=-ab

(-a)(-b)=ab

Answer 10

How can i = sqrt(-1) if no number multiply by iself is negative???

Answer 11

4 + (-4(-1))

Answer 12

Do you need a proof ?

Answer 13

You can never find sqrt -1 in the Real line, but you can do it in the imaginary one

Answer 14

explain imaginary number line pls

Answer 15

Well i have a whole dedicated thread to it let me get back to you wait.

Answer 16

Here you go my friend @Argos

http://openstudy.com/users/hba#/updates/50d885a8e4b0d6c1d5424d6f

Answer 17

tysir will chekc that out

Answer 18

If you are still not sure come back to me :)