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AP EAMCET202421 May 2024Evening ShiftMathematicsVector AlgebraActual

If a , b , c are 3 vectors such that | a |=5,| b |=8,| c |=11 and a + b + c = 0 then the angle between the vectors a and b is

Options

  1. A⁻¹ 2 5
  2. B⁻¹ 10 11
  3. C⁻¹ 41 55
  4. D3

Correct answer

A. ⁻¹ 2 5

Step-by-step solution

a + b + c = 0 a + b =- c Squaring both sides aligned & | a |^2+| b |^2+2 a b =| c |^2 & 25+64+2| a | b | =121 & (5)(8) =16 = ⁻¹ ( 2 5 ) aligned

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