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AP EAMCET201920 Apr 2019Morning ShiftMathematicsVector AlgebraActual

If the position vectors of the vertices (A, B ) and (C ) of ( A B C ) are ( i +2 j -5 k ,-2 i +2 j + k ) and (2 i + j - k ) respectively, then ( B= )

Options

  1. A( ⁻¹ ( 7 3 10 ) )
  2. B( ⁻¹ ( 8 105 ) )
  3. C( ⁻¹ ( 1 42 ) )
  4. D( ⁻¹ (- 7 3 10 ) )

Correct answer

B. ( ⁻¹ ( 8 105 ) )

Step-by-step solution

( aligned & B A =+3 i -6 k and B C =4 i - j -2 k & array l ( B)= | B A B | | B A | B C = 12+12 9+36 16+1+4 = 24 45 21 = 24 3 105 = 8 105 B= ⁻¹ ( 8 105 ) array aligned ) Hence, option (2) is correct.

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