Question
Find the shortest distance between the lines whose vector equations are
and 
Solution
The equations of two lines are
...(1)
and
...(2)
Comparing these equations with
Let S be point on line (1) with position vector
and T be point on line (2) with position vector 
so that
Let
be the S.D. vector between given lines.
Therefore, it is parallel to
If
is a unit vector along 
then
Now S.D. = Projection of
...(1)and
...(2)Comparing these equations with
Let S be point on line (1) with position vector
and T be point on line (2) with position vector so thatLet
be the S.D. vector between given lines. Therefore, it is parallel to
If
is a unit vector along thenNow S.D. = Projection of
