Why is invertible matrix full rank?
The rank of a matrix is defined by the highest order of the nonzero subformula of a matrix. The determinant of an invertible matrix is the highest nonzero subformula (of order n), so it is full rank
The rank of a matrix is defined by the highest order of the nonzero subformula of a matrix. The determinant of an invertible matrix is the highest nonzero subformula (of order n), so it is full rank