Example 3.  Solve the 31 by 31 system    in Example 1 using Mathematica's built in TridiagonalSolve[a,d,c,b] procedure.    Compute the solution using decimal arithmetic and rational arithmetic.  

Solution 3 (a).

We can compare this answer with the previous one in Examples 1 and  2.

(c) John H. Mathews 2004