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Question
If A = `[(2, 3),(a, 6)]` is a singular matrix, then a = ______.
Options
6
– 5
3
4
Solution
If A = `[(2, 3),(a, 6)]` is a singular matrix, then a = 4.
Explanation:
∵ Matrix A is a singular matrix.
∴ |A| = 0
⇒ `|(2, 3),(a, 6)|` = 0
⇒ 12 – 3a = 0
⇒ 3a = 12
⇒ a = 4.
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