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For any vector , what is ( i ) i +( j ) j +( k ) k equal to?

Options

  1. A3
  2. B-
  3. C0

Correct answer

A. 3

Step-by-step solution

=a₁ i +a₂ j +a₃ k take dot with i , j and k on both sides you get aligned & i =a₁, a₂= j , a₃= k & =( i ) i +( j ) j +( k ) k aligned

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