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MHT CET202313 May 2023Morning ShiftMathematicsVector AlgebraActual

If is angle between the vectors a and b where | a |=4, | b |=3 and ( 4 , 3 ) , then |( a - b ) ( a + b )|^2+4( a b )^2 has the value

Options

  1. A576
  2. B24
  3. C144
  4. D12

Correct answer

A. 576

Step-by-step solution

aligned & |( a - b ) ( a + b )|^2+4( a b )^2 & =|( a a )+( a b )-( b a )-( b b )|^2+4( a b )^2 & =|( a b )-( b a )|^2+4( a b )^2 & =|2( a b )|^2+4( a b )^2 [( a b )=-( b a )] & =4|( a b )|^2+4( a b )^2 & =4 [| a b |^2+( a b )^2 ] & =4| a |^2| b |^2 & =4(4)^2(3)^2 & =576 aligned

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