Show that the lines
and
intersect and find their point of intersection.
Given : Cartesian equations of lines
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To Find : distance d
Formulae :
1. Equation of line :
Equation of line passing through point A (a1, a2, a3) and having direction ratios (b1, b2, b3) is
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Where, ![]()
And ![]()
2. Cross Product :
If
are two vectors
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then,

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

Answer :
Given Cartesian equations of lines
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Line L1 is passing through point (0, 2, -3) and has direction ratios (1, 2, 3)
Therefore, vector equation of line L1 is
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And
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Line L2 is passing through point (2, 6, 3) and has direction ratios (2, 3, 4)
Therefore, vector equation of line L2 is
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Now, to calculate distance between the lines,
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Here,
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Therefore,

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Now,
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= - 2 + 8 – 6
= 0
Therefore, the shortest distance between the given lines is

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As d = 0
Hence, given lines intersect each other.
Now, general point on L1 is
x1 = λ , y1 = 2λ+2 , z1 = 3λ-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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⇒ 3λ – 6 = 4λ – 8
⇒ λ = 2
Therefore, x1 = 2 , y1 = 2(2)+2 , z1 = 3(2)-3
⇒ x1 = 2 , y1 = 6 , z1 = 3
Hence point of intersection of given lines is (2, 6, 3).