Complex number is a small mathematical utility, totally free and does not even require installation, that runs under MSDOS environment.
The mission of Complex number is to solve all kinds of complex expressions, since it allows obtaining the roots of any complex number (as long as n is less than 9) and graphically showing the behavior of that complex number.
On the other hand, Complex number also allows you to perform the following operations with complex numbers: addition, subtraction, conjugation, multiplication, division and even until you get the reciprocal.
You can free download Complex number 32, 64 bit and safe install the latest trial or new full version for Windows 10 from the official site.