Complex Numbers (C)
Complex numbers is the set of all two-dimmensional vectors having a real, and a imaginary component.
Any complex number
$z = a + bi$
Complex numbers are still numbers (not sets or pairs)
a = 1
b = 0
i = ?
$1 + 0i \equiv 1 \in N$
$z = 2e^{i\theta}$