ExamBro
ExamBro
CUET · MATHS · PYQ PAPER 2023

If \(\Delta=\) equation \(\left|\begin{array}{lll}a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33}\end{array}\right|\) and \(A_{i j}\) is the cofactor of \(a_{i j}\), then the value of \(\Delta\) is given by:

  1. A \(a_{11} A_{31}+a_{12} A_{32}+a_{13} A_{33}\)
  2. B \(a_{11} A_{11}+a_{12} A_{21}+a_{13} A_{31}\)
  3. C \(a_{21} A_{11}+a_{22} A_{12}+a_{23} A_{13}\)
  4. D \(a_{11} A_{11}+a_{21} A_{21}+a_{31} A_{31}\)
Verified Solution

Answer & Solution

Correct Answer

(D) \(a_{11} A_{11}+a_{21} A_{21}+a_{31} A_{31}\)

Step-by-step Solution

Detailed explanation

\(\Delta = a_{11} A_{11}+a_{21} A_{21}+a_{31} A_{31}\)