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AP EAMCET202423 May 2024Morning ShiftMathematicsVector AlgebraActual

If a =-4 i +2 j +4 k , b = 2 i - 2 j are two vectors then angle between the vectors 2 a and b 2 is

Options

  1. A30^
  2. B135^
  3. C90^
  4. D0^

Correct answer

B. 135^

Step-by-step solution

Angle between 2 a and b 2 aligned & = (2 a ) ( b 2 ) |2 a | | b 2 | = a b | a || b | & = -4 2 -2 2 16+4+16 2+2 = -6 2 6 2 =- 1 2 & =- 1 2 = (180^ -45^ )= 135^ =135^ aligned

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