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MHT CET202210 Aug 2022Evening ShiftMathematicsVector AlgebraActual

A unit vector a makes angles 3 with i , 4 with j and ( , ) with k , then a value of is

Options

  1. A2 3
  2. B5 12
  3. C5 6
  4. D4

Correct answer

A. 2 3

Step-by-step solution

aligned & = 3 , = 4 and =0 & ^2 + ^2 + ^2 =1 & ^2 3 + ^2 4 + ^2 =1 & 1 4 + 1 2 + ^2 =1 aligned ^2 = 1 4 = 1 2 = 3 or 2 3 as (0, )

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