R Program: Create a Matrix from a Vector of numbers

Generalizing Example 1.3, we say that a square or rectangular matrix R with entries ri j is upper-triangular if ri j=0 for i>j . By considering what space is spanned by the first n columns of R and using (1.8), show that if R is a nonsingular m ×m upper-triangular matrix, then R^-1 is also upper-triangular. (The analogous result also holds for lower-triangular matrices.) | Numerade