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MHT CET20228 Aug 2022Morning ShiftMathematicsVector AlgebraActual

If a +2 b +3 c = 0 and ( b b )+( b c )+( c a )= ( b c ) , then has the value

Options

  1. A4
  2. B5
  3. C3
  4. D6

Correct answer

D. 6

Step-by-step solution

aligned & ( a + b + c ) ( a +2 b +3 c )= 0 & 2 a b +3 a c + b a +3 b c + c a +2 c b = 0 & a b + b c -2 c a = 0 & a b + b c + c a =3 c a =3 c (-2 b -3 c ) [ from (1)] & a b + b c + c a =-6 c b & a b + b c + c a =6 b c & =6 aligned

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