Solving a tridiagonal linear system

3 = 7 10x 2 +9x 3 = 47 Now subtract 5 times equation #2 from equation #3, to eliminate x 2 from equation #3: 3x 1 +4x 2 = 11 +2x 2 +1x 3 = 7 +4x 3 = 12 The original tridiagonal equations now have a format known as upper triangular. Upper triangular systems are easy to solve. Now we do the back solve step. x 3 = 12=4 x 2 = (7 1x 3)=2 x 1 = (11 ... ................
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