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Question
Check whether the following matrices are invertible or not:
`[(1, 1),(1, 1)]`
Solution
let A = `[(1, 1),(1, 1)]`
Then, |A| = `|(1, 1),(1, 1)|`
= 1 – 1
= 0
∴ A is a singular matrix.
∴ A is not invertible.
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