Show that the lines
and
intersect.
Also, find their point of intersection.
Given equations :
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To Find : d
Formula :
1. Cross Product :
If
are two vectors
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then,

2. Dot Product :
If
are two vectors
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then,
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3. Shortest distance between two lines :
The shortest distance between the skew lines
and
is given by,

Answer :
For given lines,
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Here,
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Therefore,

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Now,
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= - 15 – 18 + 33
= 0
Therefore, the shortest distance between the given lines is

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As d = 0
Hence, the given lines not intersect each other.
Now, to find point of intersection, let us convert given vector equations into Cartesian equations.
For that substituting
in given equations,
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General point on L1 is
x1 = 2λ+1 , y1 = 3λ+2 , z1 = 4λ+3
let, P(x1, y1, z1) be point of intersection of two given lines.
Therefore, point P satisfies equation of line L2.
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⇒ 4λ – 6 = 15λ + 5
⇒ 11λ = -11
⇒ λ = -1
Therefore, x1 = 2(-1)+1 , y1 = 3(-1)+2 , z1 = 4(-1)+3
⇒ x1 = -1 , y1 = -1 , z1 = -1
Hence point of intersection of given lines is (-1, -1, -1).