NCERT Exercise 4.3 Q5 - Determinants
Question: If Delta=[aij] and Aij are cofactors, then Delta equals (A) a11 A31+a12 A32+a13 A33 (B) a11 A11+a12 A21+a13 A31 (C) a21 A11+a22 A12+a23 A13 (D) a11 A11+a21 A21+a31 A31.
Answer: (D).
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