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COMEDK2015MathematicsMatrices

If A and B are 2 matrices such that A B=A and B A=B , then B² is equal to

Options

  1. AB
  2. BA
  3. Czero matrix
  4. D1

Correct answer

A. B

Step-by-step solution

We have, B A=B aligned & (B A) B=B B B(A B)=B² & B A=B² B=B² aligned

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