Question

Q in c++ Write a program that will find the inverse of any two dimensional array without the usage of the built-in function.? plz answer in while or do while loop

Answer 1

Points to consider:

1. We need to find the determinant of the given matrix
2. Then we need to find the inverse of the matrix.

Code

#include<iostream>

using namespace std;

int main(){
   int mat[3][3], i, j;
   float determinant = 0;
  
   cout<<"Enter elements of matrix row wise:\n";
   i = 0;j=0;
   while(i<3)
   {
       j = 0;
       while(j<3)
       {
           cin>>mat[i][j];
           j++;  
       }
       i++;
   }
   printf("\nGiven matrix is:");
   i = 0;j=0;
   while(i<3){
       cout<<"\n";
       j=0;
       while(j<3){
           cout<<mat[i][j]<<"\t";
           j++;  
       }
       i++;
   }
   // This following is the calculation of the determinant.
  
   i = 0;
   while(i<3)
   {
       determinant = determinant + (mat[0][i] * (mat[1][(i+1)%3] * mat[2][(i+2)%3] - mat[1][(i+2)%3] * mat[2][(i+1)%3]));
       i++;
   }
      
   cout<<"\n\ndeterminant: "<<determinant;
  
   cout<<"\n\nInverse of matrix is: \n";
   i = 0;j= 0;
   while(i<3)
   {
       j= 0;
       while(j<3)
       {
           cout<<((mat[(j+1)%3][(i+1)%3] * mat[(j+2)%3][(i+2)%3]) - (mat[(j+1)%3][(i+2)%3] * mat[(j+2)%3][(i+1)%3]))/ determinant<<"\t";
          
           j++;
       }
       cout<<"\n";
       i++;
   }
  

return 0;
}

Output

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Thanks

- O X C:\Users\visha OneDrive Documents\C++\inverse.exe FEnter elements of matrix row wise: 3 0 2 2 0 -2 0 1 1 3 Given matrix is: © 2 120 -2 0 1 1 determinant: 10 Inverse of matrix is: -0.2 0.2 0 -0.2 0.3 1 -0.2 -0.3 0 ------------------------------- - Process exited after 95.67 seconds with return value o Press any key to continue ...