Q17 of 58 Page 77

Find A–1 if and show that

We have,

We have to find A-1 and


Firstly, we find |A|


Expanding |A| along C1, we get




= 0 – 1 {0 – 1} + 1 {1 – 0}


= 1 + 1


= 2


Now, we have to find adj A and for that we have to find co-factors:













Now, we have to show that








= A-1


Hence Proved


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