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MHT CET202123 Sep 2021Morning ShiftMathematicsVector AlgebraActual

If the vectors a =2 i +p j +4 k and b =6 i -9 j +q k are collinear, then p and q are

Options

  1. Ap =3, q =-2
  2. Bp =3, q = n 12
  3. Cp =-3, q =12
  4. Dp =-3, q =-12

Correct answer

C. p =-3, q =12

Step-by-step solution

Let a =x b aligned & 2 i +p j +4 k =6 x i -9 x j +q x j & 2=6 x x= 1 3 & p=-9 x (-9) ( 1 3 )=-3 and 4=q x=q ( 1 3 ) q=4(3)=12 aligned

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