Question

Help? Imaginary numbers:
(-6)(-7i)(8i)

Answer 1

What is (-6) * (-7) * 8 = ?

Answer 2

336

Answer 3

Good.

Answer 4

What is i * i = ?

Answer 5

1?

Answer 6

No.

The i of imaginary numbers is defined like this:

\(i = \sqrt{-1}\)

Since the square of a square root just gives you what is inside the square root, then

\(i^2 = (\sqrt{-1})^2 \)

or

\(i^2 = -1\)

Answer 7

okay

Answer 8

Now you can think of your problem like this (using the commutative and associative properties as well as knowledge of i):

\((-6)(-7i)(8i) \)

\(= (-6)(-7)(8) \times (i)(i) \)

\(= 336i^2\)

\(= 336 \times (-1) \)

\(= -336\)

Answer 9

thanks!

Answer 10

You're welcome.