grandes-ecoles 2014 QII.B.1

grandes-ecoles · France · centrale-maths1__psi Complex Numbers Argand & Loci Circle Equation and Properties via Complex Number Manipulation
Let $z \in \mathbb{C}$. We denote $\Omega_z$ the set of points in the plane with complex affixe $Z$ such that $|Z(Z-2z)| < 1$. Justify that $\Omega_z$ is a bounded subset of the plane. Is it open? closed? compact?
Let $z \in \mathbb{C}$. We denote $\Omega_z$ the set of points in the plane with complex affixe $Z$ such that $|Z(Z-2z)| < 1$.\\
Justify that $\Omega_z$ is a bounded subset of the plane. Is it open? closed? compact?