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KCET2025MathematicsVector Algebra

If a = i +2 j + k , b = i - j +4 k and c = i + j + k are such that a + b is perpendicular to c , then the value of is

Options

  1. A1
  2. B1
  3. C-1
  4. D0

Correct answer

C. -1

Step-by-step solution

aligned & ( a + b ) c & ( a + b ) c =0 & +1+2+ +4 +1=0, +1 =-1 aligned

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