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Determinants — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMathsDeterminants2 Marks
Question
If |A| = 2, where A is 2 × 2 matrix, find |adj A|.
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Answer

For any square matrix A of order n, |adj A| = |A|n-1
Given, |A| = 2
Here, order is 2
⇒ |adj A| = |2|2-1 = 2

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