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प्रश्न
Fill in the blank :
If A = `[(3, -5),(2, 5)]`, then co-factor of a12 is _______
उत्तर
If A = `[(3, -5),(2, 5)]`, then co-factor of a12 is – 2.
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Solution:
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AB = [ ]
|AB| = `square`
M11 = –2 ∴ A11 = (–1)1+1 . (–2) = –2
M12 = –3 A12 = (–1)1+2 . (–3) = 3
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