Complex NUmbers 4:Adding and Subtracting Complex Numbers

Thread Starter


Joined Jan 18, 2005
Now complex numbers as stated in a previous thread can be drawn on a diagram as a vector quantity ( with magnitude r and size θ). But how do we add together complex numbers?
It is extremely easy you just treat them like vectors, remember that with a vector you can simply add the components together for example (2i +3j +4k) + (3i + 4j + 5k) = (5i + 7j + 9k).
Test it out on your diagrams don't just accept what people tell you try it out for yourselves. Take two complex numbers
(4 + j6) and (5 + j7) we find that if we add these like vectors we are adding the components together keeping the real and j parts seperate, so we would get (9 + j13). Similarly if we were to take away two vectors we would just take away the components to get (-1 -1j) = (-1 - j) .

The next thread will describe multiplying and dividing complex numbers in the forms (a + jb) and r(Cosθ + jSinθ)