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प्रश्न
If adj(A) = `[(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`, find A–1
उत्तर
adj(A) = `[(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`
∴ |adj A| = `[(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`
Expanding along R1 –(– 2)[36 – 18]
= 2(18)
= 36
A–1 = `+- 1/sqrt(|"adj A"|)`
adj A = `+- 1/sqrt(36) [(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`
= `+- 1/6 [(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`
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