Tamilnadu +2 maths important one mark question

                                  Application of matrices and determinants - Set 3

   15. Equivalent matrices have rank ………….

   (1)    Same                                 (2)    different   

   (3)     May or may not be same    (4)    zero

   16. By determinant method the value of  ∆_x for the equations 

   x-y = 2; 3y = 3x-7 is

(1)0              (2) 1         (3)    5              (4)    8

   17.  The solution of 7x+5y-13z+4 = 0, 9x+2y+11z = 37, 3x-y+z = 2 is

   (1) x=1,y=3,z=2  (2) x=2,y=1,z=3  (3) x=3,y=2,z=1  (4) none of these

   18.  If A is a square matrix of order n, then A(adj A)

   (1) [a_ij]^T     (2)AI          (3) IAI I_n           (4) IAI

   19.  The rank  of a non-singular matrix of order n×n is

   (1)  n                (2)  n²               (3)  0                        (4)    1

   20. If the value  of  ∆_x is given , then the value of  x is 

   (1) ∆_x/∆             (2) ∆/∆_x     (3) ∆_x = 0           (4) ∆×∆_x

   21. The value of z, from the given equations:

   2x+y+z = 5; x+y+z = 4; x-y+2z = 1 is

   (1) 2                 (2) 6                 (3) 3                 (4) 1