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Question
Find the inverse of the following matrix:
`[(3,1),(-1,3)]`
Solution
Let A = `[(3,1),(-1,3)]`
∴ |A| = 9 + 1 = 5
adj A = `[(3,-1),(1,3)]`
`"A"^-1 = 1/|"A"|` adj A = `1/10[(3,-1),(1,3)]`
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