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Find the minor of element 7 in the determinant .

  1. 23
  2. -23
  3. 24
  4. -27

Answer (Detailed Solution Below)

Option 2 : -23
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Detailed Solution

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Concept:

Minor of an element aij of a determinant is the determinant obtained by deleting its ith row and jth column in which element aij lies. Minor of an element aij is denoted by Mij.

Calculation:

Given:

Since 7 lies in the second row and third column, its minor M23 is given by:

= 9 - 32

= -23

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