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If $\triangle=\begin{vmatrix}a_{11}&a_{12}&a_{13}\\a_{21}&a_{22}&a_{23}\\a_{31}&a_{32}&a_{33}\end{vmatrix}$ and $A_{ij}$ is cofactors of $a_{ij},$ then value of $\triangle$ is given by:

• A
  $a_{11}A_{31} + a_{12}A_{32} + a_{13}A_{33}$
• B
  $a_{11}A_{11} + a_{12}A_{21} + a_{13}A_{31}$
• C
  $a_{21}A_{11} + a_{22}A_{12} + a_{23}A_{13}$
• ✓
  $a_{11}A_{11} + a_{21}A_{21} + a_{31}A_{31}$