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NDA2019MathematicsMatricesActual

If A= ( array ll 1 & 2 2 & 3 3 & 4 array ) and B= ( array ll 1 & 2 2 & 1 array ) , then which one of the following is correct?

Options

  1. ABoth AB and BA exist
  2. BNeither AB nor BA exists
  3. CAB exists but BA does not exist
  4. DAB does not exist but BA exists

Correct answer

C. AB exists but BA does not exist

Step-by-step solution

A= [ array ll 1 & 2 2 & 3 3 & 4 array ] ; B= [ array ll 1 & 2 2 & 1 array ] Order of A=3 2 Order of B=2 2 by fundamental properties we can say A B exists while B A does not exist.

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