Question

Find the inverse of the matrix .

Solution

Correct option is

– 2

We have   

   

       , expanding the determinant along the first

        = –2.  

   

Now the cofactors of the elements of the first row of

           

i.e., are –1, 8, –5 respectively.  

The cofactors of the elements of the second row of

            

i.e., are 1, –6 3 respectively. 

The cofactors of the elements of the their row of 

            

i.e., are –1, 2, –1 respectively. 

Therefore the Adj. A = the transpose of the matrix B where 

                 

  

SIMILAR QUESTIONS

Q1

then the number of solutions of the system of equations

      

Q4

For what value of k do the following homogeneous system of equations possess a non-trivial solution ? 

          

          

          

Q5

Find value of  for which the set of equations  

           

           

          

are consistent.    

Q6
Q7

Find the product of the matrices

       .

Q10

If A and B are any 2 × 2 matrices, then det (A + B) = 0 implies