Show that the lines and
do not intersect.
Given: - Two lines equation: and
To find: - Intersection point
We have,
⇒ x = 3λ + 1, y = 2λ – 1 and z = 5λ + 1
So, the coordinates of a general point on this line are
(3λ + 1, 2λ – 1, 5λ + 1)
The equation of the 2nd line is
⇒ x = 4μ – 2, y = 3μ + 1 and z = – 2μ – 1
So, the coordinates of a general point on this line are
(4μ – 2, 3μ + 1, – 2μ – 1)
If the lines intersect, then they must have a common point.
Therefore for some value of λ and μ, we have
⇒ 3λ + 1 = 4μ – 2 , 2λ – 1 = 3μ + 1, and 5λ + 1 = – 2μ – 1
⇒ ……(i)
⇒ 2λ – 3μ = 2 ……(ii)
and 5λ + 2μ = – 2 ……(iii)
putting value of λ from eq i in eq ii, we get
⇒ – μ = 12
⇒ μ = – 12
Now putting value of μ in eq i, we get
⇒
⇒
⇒ λ = – 17
As we can see by putting value of λ and μ in eq iii, that it does not satisfy the equation.
Check
LHS
= 5λ + 2μ
= 5( – 17) + 2( – 12)
= – 85 – 24
= – 109
≠ RHS
Hence intersection point does not exist or line do not intersects