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If the value of a third order determinant is 12, then the value of the determinant formed by replacing each element by its co-factor will be 144. - Mathematics

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प्रश्न

If the value of a third order determinant is 12, then the value of the determinant formed by replacing each element by its co-factor will be 144.

विकल्प

  • True

  • False

MCQ
सत्य या असत्य
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उत्तर

This statement is True.

Explanation:

Since |A| = 12

If A is a square matrix of order n

Then |Adj A| = `|"A"|^("n" - 1)`

∴ |Adj A| = `|"A"|^(3 - 1)`

= |A|2

= (12)2

= 144   ...[n = 3]

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अध्याय 4: Determinants - Exercise [पृष्ठ ८४]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 4 Determinants
Exercise | Q 52 | पृष्ठ ८४

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