Determining graphical set of solutions for complex numbers

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TheChemist_
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Homework Statement


So we have been doing complex numbers for about 2 weeks and there is this one equation I just can't solve.
It's about showing the set of solutions in graphical form (on "coordinate" system with the imaginary and the real axis). So here is the equation:

Homework Equations


|(z+i)/z| < 1

The Attempt at a Solution


Well, I just don't know how to solve this "thing":biggrin:
The only thing we did was to picture some other solutions...

I hope you can help me with this little problem!
Thx
 
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TheChemist_ said:

Homework Statement


So we have been doing complex numbers for about 2 weeks and there is this one equation I just can't solve.
It's about showing the set of solutions in graphical form (on "coordinate" system with the imaginary and the real axis). So here is the equation:

Homework Equations


|(z+i)/z| < 1

The Attempt at a Solution


Well, I just don't know how to solve this "thing":biggrin:
The only thing we did was to picture some other solutions...

I hope you can help me with this little problem!
Thx

Write it as ##|z+i| < |z|##.

What are the graphical/geometric interpretations of the quantities ##|z+i|## and ##|z|##?
 
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jedishrfu said:
Checkout Geogebra, its an educational software tool for students and it may be able to help you learn more about complex numbers.

https://www.geogebra.org/

yeah I know geogebra and I use it quite often, but I haven't been able to figure out how I can view complex numbers...
 
Ray Vickson said:
Write it as ##|z+i| < |z|##.

What are the graphical/geometric interpretations of the quantities ##|z+i|## and ##|z|##?

Ok that made things a little clearer...but i still can't figure out how |z+i| could look...
 
TheChemist_ said:
Ok that made things a little clearer...but i still can't figure out how |z+i| could look...
|z + i| is the same as |z - (-i)|; i.e. the distance between a complex number z and the imaginary number -i. |z| represents the distance from the same z to the origin.
Edit: Fixed typo pointed out by SammyS.
 
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Ok thanks guys I managed to solve it!