# How do you evaluate a norm like this?

1. Apr 28, 2012

### GridironCPJ

‖A(x+αz)-b‖_2^2

where A is an mxn matrix, x and z are vectors in R^n, b is a vector in R^m, and α is a scalar.

2. Apr 30, 2012

### Office_Shredder

Staff Emeritus
I don't really understand the question. A(x+αz)-b is a vector in Rm, so you just calculate its norm