1 files changed, 54 insertions, 0 deletions
diff --git a/260/CH3/EX3.13/3_13.sce b/260/CH3/EX3.13/3_13.sce
new file mode 100644
index 000000000..1f0bc748b
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+++ b/260/CH3/EX3.13/3_13.sce
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+//Eg-3.13
+//pg-102
+
+clear
+clc
+
+ A=[1 1 -1;1 2 -2;-2 1 1];
+ B=[1;0;1];
+ 
+n=3;
+
+Z=A;
+Y=B;
+I=[1 0 0;0 1 0;0 0 1];//creates an identity matrix of size n*n
+X=zeros(3,1);
+inverse=zeros(3,3);
+ABI=zeros(3,7);
+ABI(:,:)=[A(:,:) B(:,:) I(:,:)];//augumented matrix of A,B,I
+  for k=1:n//proceeds from 1st row to the last row
+        u=k;
+        big=abs(ABI(k,k));          
+        for t=k+1:n  //this loop is for selecting the elementhaving max absolute value in a column                   
+        dummy=abs(ABI(t,k));     
+        if dummy>big
+            big=dummy;
+            u=t;
+        end
+    end
+        if u~=k
+        for j=1:2*n+1//interchanging rows to make max absolute element as pivot 
+            dummy=ABI(u,j);
+            ABI(u,j)=ABI(k,j);
+            ABI(k,j)=dummy;
+        end
+        end
+        pivot=ABI(k,k);
+        
+        ABI(k,:)=ABI(k,:)/pivot;
+       
+        for i=1:n
+            if i~=k;
+            factor=ABI(i,k);
+            ABI(i,:)=ABI(i,:)-ABI(k,:)*factor;
+           
+        end
+    end
+    X(:,:)=[ABI(:,n+1)];//determining X using augumented matrix
+    inverse(:,:)=[ABI(:,n+2:2*n+1)];//calculating inverse using augmented matrix
+end
+ 
+ 
+ disp("result")
+ disp(inverse)
+            
+\ No newline at end of file