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If A= [ array cc & - & array ] then what is AA ^T equal to (where A ^ T is the transpose of A ) ?

Options

  1. ANull matrix
  2. BIdentify matrix
  3. CA
  4. D-A

Correct answer

B. Identify matrix

Step-by-step solution

aligned & A= [ array cc & - & array ] & A A^T= [ array cc & - & array ] [ array cc & - & array ] aligned aligned & = [ array cc ^2 + ^2 & - + - + & ^2 + ^2 array ] & = [ array ll 1 & 0 0 & 1 array ] aligned

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