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Question
Choose the correct alternative.
If A = `[("a", 0, 0),(0, "a", 0),(0, 0,"a")]`, then |adj.A| = _______
Options
a12
a9
a6
a–3
Solution
adj A = `[("a"^2, 0, 0),(0, "a"^2, 0),(0, 0,"a"^2)]`
∴ |adj A| = `[("a"^2, 0, 0),(0, "a"^2, 0),(0, 0,"a"^2)]`
= a6.
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