Let 0 and A= [ array rrr & & 3 & & - & & 2 array ] . If B= [ array rrr 3 & -9 & 3 - & 7 & -2 -2 & 5 & -2 array ] is the matrix of cofactors of the elements of A , then det (A B) is equal to :

Step-by-step solution

Equating co-factor fo A ₂₁ aligned & (2 ^2-3 )= & =0,2 (accept) aligned Now, 2 ^2- =3 aligned & =2 =1 & | AB |=| A cof ( A )|=| A |^3 & ~A = | array lll 1 & 2 & 3 2 & 2 & 1 -1 & 2 & 4 array |=6-2(9)+3(6)=6 aligned