Let $\mathbb{C}$ be the D372: Set of complex numbers.
Let $\pm$ be the D606: Real addition operation.
The complex addition operation is the D554: Binary operation \begin{equation} + : \mathbb{C} \times \mathbb{C} \to \mathbb{C}, \quad (a, b) + (c, d) = (a \pm c, b \pm d) \end{equation}