Question

The characteristic roots of unitary matrix are of unit modulus

Answer 1

Step-by-step explanation:

$$AA^*=A^*A=I$$

where $A^*$ is the conjugate transpose of $A$, and $I$ is the identity matrix. Furthermore, for a square matrix $A$, the eigenvalue equation is expressed by $$Av=\lambda v$$

If I use the relationship $u v=v^*u$ and take the conjugate transpose of this equation then $$v^*A^*=\lambda^*v^*$$