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Let A= [ array ccc 5 & 5 & 0 & & 5 0 & 0 & 5 array ] . If |A^2 |=25 , then | | equals

Options

  1. A5^2
  2. B1
  3. C1 / 5
  4. D5

Correct answer

C. 1 / 5

Step-by-step solution

A ^2= [ array ccc 5 & 5 & 0 & & 5 0 & 0 & 5 array ] [ array ccc 5 & 5 & 0 & & 5 0 & 0 & 5 array ] A ^2= [ array ccc 25 & 25 +5 ^2 & 5 +25 ^2+5 0 & ^2 & 5 ^2+25 0 & 0 & 25 array ]625 ^2=25 | |= 1 5 .

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