What is a complex conjugate?

1 Answer
Bernardo Russo G. Ferreira
Oct 3, 2014

A complex conjugate is the number to which you have to multiply a complex number in order to make it real.
By using the identity (x+y) . (x-y) = x²-y², we see that, to every complex, there is another to which we can multiply it in order to get a new number that will not depend on i.
If (a+bi).(c+di) is real, (c+di) is (a+bi)'s conjugate and it equals (a-bi).

Related questions
See all questions in Complex Conjugate Zeros
Impact of this question
7495 views around the world
You can reuse this answer
Creative Commons License