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Question
If A is a matrix of order 3 × 3, then (A2)–1 = ______.
Solution
If A is a matrix of order 3 × 3, then (A2)–1 = (A–1)2.
Explanation:
(A2)–1 =`(A" * "A")^-1`
= `"A"^-1 * "A"^-1` .....(As (AB)–1 = B–1A–1)
= (A–1)2
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