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


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