1 files changed, 21 insertions, 0 deletions
diff --git a/964/CH9/EX9.12/9_12.sce b/964/CH9/EX9.12/9_12.sce
new file mode 100755
index 000000000..9cf03f03d
--- /dev/null
+++ b/964/CH9/EX9.12/9_12.sce
@@ -0,0 +1,21 @@
+//clc()
+//3*x1 - 0.1*x2 - 0.2*x3 = 7.85
+//0.1*x1 + 7*x2 - 0.3*x3 = -19.3
+//0.3*x1 - 0.2*x2 + 10*x3 = 71.4
+// this can be written in matrix form as
+A = [3,-0.1,-0.2,7.85;0.1,7,-0.3,-19.3;0.3,-0.2,10,71.4];
+disp(A,"Equation in matrix form can be written as")
+X = A(1,:) / det(A(1,1));
+Y = A(2,:) - 0.1*X;
+Z = A(3,:) - 0.3*X;
+Y = Y/det(Y(1,2));
+X = X - Y * det(X(1,2));
+Z = Z - Y * det(Z(1,2));
+Z = Z/det(Z(1,3));
+X = X - Z*det(X(1,3));
+Y = Y - Z*det(Y(1,3));
+A = [X;Y;Z];
+disp(A,"final matrix = ")
+disp(det(A(1,4)),"x1 = ")
+disp(det(A(2,4)),"x2 = ")
+disp(det(A(3,4)),"x3 = ")