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AP EAMCET20226 Jul 2022Evening ShiftMathematicsVector AlgebraActual

The vectors a =2 i +3 j +6 k and b are collinear and | b |=2 l , then b =

Options

  1. A(2 i +3 j +6 k )
  2. B(6 i +9 j +18 k )
  3. C21 3 ( i +. j + k )
  4. D21(2 i +3 j +6 k )

Correct answer

B. (6 i +9 j +18 k )

Step-by-step solution

If a and b are collinear, then aligned & b = a & | b |=| || a | & 21=| | 4+9+36 & | |= 21 7 | |=3 & = 3 & b = 3(2 i +3 j +6 k )= (6 i +9 j +18 k ) & aligned

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