Question

Which of the following is equivalent to the complex number -8(7i - 3i^2)

A) -80i
B) -56i - 24
C) -56 + 24i
D) -32i

Answer 1

Answer: B) -56i - 24

This is the same as -24 - 56i

=============================================

Step-by-step explanation:

The 'i' refers to the imaginary number
`√(-1)`

In other words,
`i = √(-1)`

Squaring both sides gets us
`i^2 = -1`

So,

`x = -8(7i - 3i^2)\\\\x = -8(7i - 3(-1))\\\\x = -8(7i + 3)\\\\x = -8(7i) -8(3)\\\\x = -56i -24 \ \ \text{ .... Answer: Choice B}\\\\x = -24 - 56i\\\\`

The result is in the form a+bi where a = -24 is the real part and b = -56 is the imaginary part.