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Question
Find the position vector of the mid point of the vector joining the points P (2, 3, 4) and Q (4, 1, – 2).
Solution
The midpoints measuring the points P(2, 3, 4), Q(4, 1, -2).
`vec("OR") = ((2hati + 3hatj + 4hatk) + (4hati + hatj - 2hatk))/2`
= `((2 + 4)hati + (3 + 1)hatj + (4 - 2)hatk)/2`
= `(6hati + 4hatj + 2hatk)/2`
`= 3hati + 2hatj + hatk`
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