Since AD is the median 
∴D=(2λ−1,4,2μ+2) Now, dR's of AD is a=(2λ−1−2)=2λ−5 b=4−3=1,c=2μ+2−5=2μ−8 Also, a,b,c are dR 's ∴a=kl,b=km,c=kn where l=m=n and l2+m2+n2=1 ⇒l=m=n=31 Now, a=1,b=1 and c=1 ⇒λ=7 and μ=10
JEE Main 2013 — Mathematics Vectors & 3D Geometry
Let ABC be a triangle with vertices at points A (2,3,5), B (−1,3,2) and C(λ,5,μ) in three dimensional space. If the median through A is equally inclined with the axes, then (λ,μ) is equal to:
Held on 25 Apr 2013 · Verified 6 Jul 2026.
(10,7)
(7,5)
(7,10)
(5,7)
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