# Question: let a belong to cmxn show that uaf avf...

###### Question details

Let A belong to C^{mxn}. Show that ||UA||_{F} =
||AV||_{F} = ||A||_{F} for any unitary matrices U
belong to C^{mxm} and V belong to C^{nxn}. Here,
||.||_{F} stands for Frobenius norm.