# How do you find the complex conjugate of 2 - 4i?

Dec 5, 2015

$2 + 4 i$

#### Explanation:

The complex conjugate of the complex number $a + b i$ is simply $a - b i$.

In other words, change the sign of the term with the $i$: if it's positive, make it negative; if it's negative, make it positive.

Thus, the complex conjugate of $2 \textcolor{red}{-} 4 i$ is $2 \textcolor{red}{+} 4 i$.