Complex Number in Cartesian Form
## Formula
$$z=x+iy$$
If:
$$z=r(\cos\theta+i\sin\theta)$$
then:
$$x=r\cos\theta$$
$$y=r\sin\theta$$
and:
$$r=\sqrt{x^2+y^2}$$
## Conditions / Special Cases
$$x=\operatorname{Re}(z)$$
$$y=\operatorname{Im}(z)$$
$$r=|z|$$
## Usage
- Used to convert between Cartesian and polar representations.