Question

Which of the following is the conjugate of a complex number with −4 as the real part and 2 as the imaginary part?

2i − 4

2i + 4

−4 − 2i

−4 + 2i

Answer 1

complex conjugate means negate the imaginary component.

example: if you have a+ bi then complex conjugate is a - bi
if you have a - bi, then the complex conjugate is a+bi

or, using numbers:
1-2i complex conjugate is 1+2i
(btw, we usually write the real part first, then the imaginary part... though this does not change the number)

Answer 2

with complex conjugate you know the *real part does not change*

Answer 3

ok cool thanks man @phi