# What is the complex conjugate of -1+2sqrt(2i)?

$- 1 - 2 \sqrt{2} i$
For any complex number in rectangular form $z = x + i y$, the complex conjugate is $\overline{z} = x - i y$.
Note that $z \overline{z} = {x}^{2} + {y}^{2} \in \mathbb{R}$