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

1. √18
2. √72
3. √33
4. √45

Correct answer: √33

Solution

The length of the median from vertex A to the midpoint of side BC can be calculated using the formula for the median in a triangle, which involves the lengths of the sides. By applying the median formula and simplifying, we find that the length of the median through A is √33.

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