# How do you write the complex conjugate of the complex number (7A + 3B - 4i)?

$\left(7 A + 3 B + 4 i\right)$.
The Complex Conjugate of $\left(x + i y\right)$ is $\left(x - i y\right)$, &, vise-versa.
Therefore, the reqd. coj. of $\left(7 A + 3 B - 4 i\right)$ is $\left(7 A + 3 B + 4 i\right)$.