Question

Which expression represents the number −3i^4+2i^3+2i^2+\sqrt(-9) rewritten in a+bi form?

A) −1−i
B)−1+5i
C)−5+i
D)−5−5i
E)−5−i

Answer 1

Answer: Option C

`-5+i`

Explanation:

We have the following complex number

`-3i^4+2i^3+2i^2+√(-9)`

Remember that by definition
`i=√(-1)` so
`i^2 = -1`

Then we simplify the expression:

`-3(i^2)^2+2(i^2*i)+2i^2+√(9)*√(-1)`

`-3(-1)^2+2((-1)*i)+2(-1)+√(9)*i`

`-3-2i-2+3*i`

`-5+i`

The answer is the option C