Let A be a point on the line =(1-3μ ) i+(μ -1) j+(2+5μ ) k and B(3, 2, 6) be a point in the space. Then the value of μ for which the vector AB is…
JEE Main 2019 — Mathematics Vectors & 3D Geometry
2019mcqeasy
Let A be a point on the line r=(1−3μ)i^+(μ−1)j^+(2+5μ)k^ and B(3,2,6) be a point in the space. Then the value of μ for which the vector AB is parallel to the plane x−4y+3z=1 is
Official previous-year question
Held on 10 Jan 2019 · Verified 6 Jul 2026.
Options
A
21
B
41
C
−41
D
81
Did you get this right?
Sign in to track your attempts and accuracy.
Solution
Let A is (1−3μ,μ−1,2+5μ)
We know that the vector joining two points (x1,y1,z1) and (x2,y2,z2) is (x2−x1)i^+(y2−y1)j^+(z2−z1)k^
⇒AB=(3μ+2)i^+(3−μ)j^+(4−5μ)k^ which is parallel to plane x−4y+3z=1
⇒1(3μ+2)−4(3−μ)+3(4−5μ)=0
⇒3μ+2−12+4μ+12−15μ=0
⇒−8μ+2=0
⇒μ=41.
Your note
Sign in to keep a private note on this question. Nothing you write is ever public.