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AP EAMCET202124 Aug 2021Evening ShiftMathematicsVector AlgebraActual

If a is a vector of magnitude 7, b is a vector of magnitude 8 , then the maximum value of | a b | is

Options

  1. A5 and ( a b )= 6
  2. B28 and ( a b )= 3
  3. C56 and ( a b )= 2
  4. D56 and ( a b )=

Correct answer

D. 56 and ( a b )=

Step-by-step solution

Given, | a |=7 and | b |=8 a b =| a || b | aligned & | a b |=| a || b | & | a b |=7 8| | & | a b |=56| | aligned | a b | is maximum when = and maximum value is 56.

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