A circle of radius \(\displaystyle R\) around a complex number \(\displaystyle z_0\in\mathbb{C}\) is defined to be \(\displaystyle \left\{z\in\mathbb{C}:|z-z_0|=R\right\}\)

A circle of radius \(\displaystyle R\) around a complex number \(\displaystyle z_0\in\mathbb{C}\) is defined to be \(\displaystyle \left\{z\in\mathbb{C}:|z-z_0|=R\right\}\)