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AP EAMCET202018 Sep 2020Morning ShiftMathematicsVector AlgebraActual

If ( ) is the angle between two vectors ( p =3 i +4 j - k ) and ( q =2 i - j + k ), then ( ( )= )

Options

  1. A( 145 156 )
  2. B( 135 156 )
  3. C( 155 156 )
  4. D( 165 156 )

Correct answer

C. ( 155 156 )

Step-by-step solution

If ( ) is an acute angle between vectors (p ) and (q ), then ( aligned Sin & = | p q | | p || q | = (4-1)^2+(-3-2)^2+(-3-8)^2 9+16+1 4+1+1 & = 9+25+121 156 = 155 156 aligned )

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