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Question
Find the inverse (if it exists) of the following:
`[(-2, 4),(1, -3)]`
Solution
`[(-2, 4),(1, -3)]`
|A| = 6 – 4
= 2 ≠ 0
∴ A-1 exists. A is non singular.
adj A = `[(-3, -4),(1, -2)]`
A-1 = `1/|"A"|`
adj A = `1/2[(-3, -4),(1, -2)]`
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