AP EAMCET20226 Jul 2022Evening ShiftMathematicsMatricesActual

If A= [ array cc & - & array ] and A+A⁻¹=I , then =

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Correct answer

C. 6

Step-by-step solution

Given, aligned A & = [ array cc & - & array ] Adj A & = [ array cc & - & array ] |A| & = ^2 + ^2 =1 A⁻¹ & = [ array cc & - & array ] A+A⁻¹ & = [ array cc & - & array ]+ [ array cc & - & array ] & = [ array cc 2 & 0 0 & 2 array ] A+A⁻¹ & =I, if 2 =1 & = 1 2 = 6 aligned

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