question_answer 70)

If A  find A?1.       Using A?1 solve the system of equations.       2x ? 3y + 5z = 11; 3x + 2y ? 4z = ?5; xs + y ? 2z = ?3  

Answer:

      = 2(?4 + 4) + 3 (?6 + 4) + 5 (3 ? 2)       = 0 ? 6 + 5 = ? 1  0       Therefore A is non-singular matrix so A?1 exists.       A11 = 0; A12 = 2; A13 = 1       A21 = ?1; A22 = ?9; A23 = ?5       A31 = 2; A32 = 23; A33 = 13       Adj  A =                               The given system can be expressed as AX = B, where       Now AX = B                   On equating, we get x = 1, y = 2 and z = 3.