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AP EAMCET2012MathematicsVector Algebra

a = i + j -2 k ( a i ) j ^2 is equal to

Options

  1. A6
  2. B6
  3. C36
  4. D6 6

Correct answer

B. 6

Step-by-step solution

Given, a = i + j -2 k aligned & [( a i ) j ]^2= [( a j ) i ]^2 & = a ^2=| i + j -2 k |^2 & =( 1+1+4 )^2=6 aligned

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