in matlab

13. For a (2n) x (2n) tridiagonal system, write and test a procedure that proceeds as follows: In the forward elim- ination phase, the routine simultaneously eliminates the elements in the subdiagonal from the top to the middle and in the superdiagonal from the bottom to the middle. In the back substitution phase, the unknowns are deter- mined two at a time from the middle outward. 13. For a (2n) x (2n) tridiagonal system, write and test a procedure that proceeds as follows: In the forward elim- ination phase, the routine simultaneously eliminates the elements in the subdiagonal from the top to the middle and in the superdiagonal from the bottom to the middle. In the back substitution phase, the unknowns are deter- mined two at a time from the middle outward