Question #8380d

1 Answer
Feb 27, 2018

Did you mean to put the negative sign after the divide sign?
If so, (4-3i+2+6i)/-((3-i)(3-i))=-3/10-3/5i.

Explanation:

First, simplify the numerator by combining the integer terms and combining the i terms: 4-3i+2+6i=3i+6.

Secondly, the denominator: -((3-i)(3-i))=-(9-3i-3i+i^2). Since i=sqrt(-1), i^2=(sqrt(-1))^2=-1.
Plugging that into the denominator and combining like terms, we get -(9-6i+(-1))=-(8-6i)=-8+6i=6i-8

Our fraction is now (3i+6)/(6i-8)

This may be okay for your teacher, but the standard form for complex numbers is a+-bi, so let's get our answer in that format by multiplying the numerator and denominator by the conjugate of the denominator: ((3i+6)(6i+8))/((6i-8)(6i+8))
We get (18i^2+24i+36i+48)/(-36-64)=(30+60i)/-100 and put it in the form of a+-bi then reduce it:
30/-100-(60i)/-100=-3/10-3/5i

Hope that helps! Have fun; imaginary numbers are cool!