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MHT CET202015 Oct 2020Morning ShiftMathematicsVector AlgebraActual

If a , b , c are non-negative distinct numbers and a + a + c k , + k and c + c + b k are coplanar vectors, then

Options

  1. Aa , c , b are in A.P.
  2. Ba , b , c are in G.P.
  3. Ca , c , b are in G.P.
  4. Da , b , c are in A.P.

Correct answer

C. a , c , b are in G.P.

Step-by-step solution

Given vectors are coplanar. array l | array lll a & a & c 1 & 0 & 1 c & c & b array |=0 a (0- c )- a ( b - c )+ c ( c -0)=0 - ac - ab + ac + c ²=0 c ²= ab a , c , b are in G.P. array

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