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Question
Check whether the following matrices are invertible or not:
`[(3, 4, 3),(1, 1, 0),(1, 4, 5)]`
Solution
Let A = `[(3, 4, 3),(1, 1, 0),(1, 4, 5)]`
Then, |A| = `|(3, 4, 3),(1, 1, 0),(1, 4, 5)|`
= 3(5 – 0) – 4(5 – 0) + 3(4 – 1)
= 15 – 20 + 9
= 4 ≠ 0
∴ A is a non-singular matrix.
∴ A is invertible.
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