# Complex numbers in the form a+bi

## Homework Statement

How would I go about solving 1/z=(-4+4i)

The answer that I keep on getting is wrong

## The Attempt at a Solution

[/B]
What I did

z=1/(-4+4i)x(-4-4i)/(-4-4i)

z=(-4-4i)/(16+16i-16i-16i^2)

z=(-4-4i)/32

z=-1/8-i/8

This is the answer that I got however it says that it is wrong. I am unsure what else I can do

Thanks for any help

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ehild
Homework Helper

## Homework Statement

How would I go about solving 1/z=(-4+4i)

The answer that I keep on getting is wrong

## The Attempt at a Solution

[/B]
What I did

z=1/(-4+4i)x(-4-4i)/(-4-4i)

z=(-4-4i)/(16+16i-16i-16i^2)

z=(-4-4i)/32

z=-1/8-i/8

This is the answer that I got however it says that it is wrong. I am unsure what else I can do

Thanks for any help
Your result is right, but you might write it in the form $-\frac{1}{8}- \frac{1}{8} i$

Your result is right, but you might write it in the form $-\frac{1}{8}- \frac{1}{8} i$
Thanks! I thought I was right, the online quiz that we have must have a mistake then

chwala
Gold Member
Complex numbers $z$, have to be expressed in the form $z= a+bi$, where $a, b$, are real numbers, this was missing in your solution, the $"i"$

Mark44
Mentor
Complex numbers $z$, have to be expressed in the form $z= a+bi$, where $a, b$, are real numbers, this was missing in your solution, the $"i"$
No, it was there. This is what the OP wrote:
z=-1/8-i/8

ehild
Homework Helper
Thanks! I thought I was right, the online quiz that we have must have a mistake then
Maybe you should write 0.125 instead of 1/8.