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MHT CET202310 May 2023Evening ShiftMathematicsVector AlgebraActual

If ( a b ) c =-5 a +4 b and a b =3 , then the value of a ( b c ) is

Options

  1. A3 b -4 c
  2. B4 a -3 b
  3. C4 b -3 c
  4. D3 a -4 c

Correct answer

C. 4 b -3 c

Step-by-step solution

aligned & ( a b ) c =( a c ) b -( b c ) a & But, ( a b ) c =-5 a +4 b & -5 a +4 b =( a c ) b -( b c ) a aligned Comparing, we get aligned a c =4 & a ( b c ) & =( a c ) b -( a b ) c & =4 b -3 c [ a b =3 (given) ] aligned

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