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KCET2018MathematicsVector Algebra

If the vector ( a i + j + k , i +b j + k ) and ( i + j +c k ) are colpanar ( (a b c 1) ), then the value of ( a b c-(a+b+c)= )

Options

  1. A( 12 )
  2. B( -2 )
  3. C( 00 )
  4. D( -1 )

Correct answer

B. ( -2 )

Step-by-step solution

Given vectors, ( a i + j + k , i +b j + k ) and ( i + j +c k ) For vectors to be coplanar [ array l | array lll a & 1 & 1 1 & b & 1 1 & 1 & c array |=0 a(b c-1)-1(c-1)+1(1-b)=0 a b c-a-c+2+1-b=0 a b c-(a+b+c)=-2 array ]

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