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AP EAMCET202021 Sep 2020Morning ShiftMathematicsVector AlgebraActual

Let ( u =-2 i +2 j + k ) and ( v = i -2 j +2 k ). Then angle between ( u ) and ( v ) is

Options

  1. A( ⁻¹ ( 4 9 ) )
  2. B( ⁻¹ ( -4 3 ) )
  3. C( ⁻¹ ( 4 3 ) )
  4. D( ⁻¹ ( -4 9 ) )

Correct answer

A. ( ⁻¹ ( 4 9 ) )

Step-by-step solution

Let angle between vector ( u =-2 i +2 j + k ) and ( v = i -2 j +2 k ) is ( ), then ( aligned & = | u v | | u || v | = |-2-4+2| 4+4+1 1+4+4 = 4 9 & = ⁻¹ ( 4 9 ) aligned ) Hence, option (a) is correct.

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