Find the shortest distance between the lines whose vector equations are
ˆ
ˆ
ˆ
(1
)
(
2)
(3
2 )
r
t i
t
j
t k
=
−
+
−
+
−
r
 and
ˆ
ˆ
ˆ
(
1)
(2
1)
(2
1)
r
s
i
s
j
s
k
=
+
+
−
−
+
r
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THREE D IMENSIONAL G EOMETRY
479
11 6  Plane
A plane is determined uniquely if any one of the following is known:
(i)
the normal to the plane and its distance from the origin is given, i e , equation of
a plane in normal form