I've created a new lesson on the algebra page. This calculator takes 2 complex numbers in the form a + bi and c + di and adds, subtracts, multiplies, or divides them. In addition, this calculator can take the square root of the first complex number a + bi.
Finally, the calculator has a random problem generator if you run out of homework problems to do with respect to this lesson.
It is searchable by Adds, Subtracts, Multiplies, Divides, complex, numbers, Square Root, problem. Let me know if you want enhancements or see errors.
www.mathcelebrity.com/complexnum.php
Enjoy.