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A vector b is collinear with the vector a =(2,1,-1) and satisfies the condition a b =3 . What is b equal to?

Options

  1. A(1,1 / 2,-1 / 2)
  2. B(2 / 3,1 / 3,-1 / 3)
  3. C(1 / 2,1 / 4,-1 / 4)
  4. D(1,1,0)

Correct answer

A. (1,1 / 2,-1 / 2)

Step-by-step solution

aligned & b = a & b =2 i + j - k & a =2 i + j - k & a b =4 + + =6 =3 & or = 1 2 b = ( i + 1 2 j - 1 2 k ) & = (1+ 1 2 ,- 1 2 ) aligned

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