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AP EAMCET202017 Sep 2020Morning ShiftMathematicsVector AlgebraActual

If ( a = i +3 j -6 k ) and ( b =2 i - j + k ), then the values of ( , ) so that ( a ) and ( b ) may be collinear are

Options

  1. A((5,3) )
  2. B((6,2) )
  3. C((2,-6) )
  4. D((-6,2) )

Correct answer

D. ((-6,2) )

Step-by-step solution

( a = i +3 j -6 k , b =2 i - j + k ) For (a) and (b) may be collinear (( a b )=0 ) ( array lcc & | array ccc i & j & k & 3 & -6 2 & -1 & array |=0 & i (3 -6)- j ( +12)+ k (- -6)=0 (3 -6)=0,( +12)=0 and ( +6)=0 ( =2),( =-6) array )

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