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If the vectors AB → = 3 i ^ + 4 k ^ and AC → = 5 i ^ - 2 j ^ + 4 k ^ are the sides of a triangle A B C , then the length of the median through A is:

Options

  1. A3 3
  2. B4 5
  3. C1 8
  4. D7 2

Correct answer

A. 3 3

Step-by-step solution

Length of median = AB → + AC → 2 = 8 i ^ - 2 j ^ + 8 k ^ 2 = 3 3

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