Since you already have defined \( A \) and \( V \) (these are stored as \( (N+1)\times (N+1) \) matrices) The final equation involves only the unknown \( R \). We obtain it by matrix inversion, i.e., $$ \begin{equation} R=A^{-1}V. \tag{21} \end{equation} $$ Thus, to obtain \( R \), you will need to set up the matrices \( A \) and \( V \) and invert the matrix \( A \). With the inverse \( A^{-1} \), perform a matrix multiplication with \( V \) results in \( R \).