Matrix, Dimensions.
matrix be nL by nL minus 1. Now, let’s think about the dimension of this vector B. This is going to be a 3 by 1 vector, so you have to add that to another 3 by 1 vector in order to get a 3 by 1 vector as the output. This was going to be 5 by 1, so there’s going to be another 5 by 1 vector in order