# Math Help - Householder matrices

1. ## Householder matrices

I'm given a 3x1 Householder vector (u) and a 3x2 matrix (A). The problem asks to find both HA and AH (where H is the associated Householder matrix). But how does AH even exist? The associated Householder matrix is 3x3.

2. Originally Posted by Random Variable
I'm given a 3x1 Householder vector (u) and a 3x2 matrix (A). The problem asks to find both HA and AH (where H is the associated Householder matrix). But how does AH even exist? The associated Householder matrix is 3x3.
I agree that it looks like a mistake. Perhaps it was meant to be $A^TH$.