
O is orthocentre and G is centroid and C is circumcentre. G divides OC in 2:1 ratio.
Position vector of centriod G=3a+b+c
Position vector of circum center C=4a+b+c
Apply Section Formula,
G=32C+R
3G=2C+R
R=3G−2C=(a+b+c)−2(4a+b+c)
=2a+b+c
JEE Main 2016 — Mathematics Vectors & 3D Geometry
Let ABC be a triangle whose circumcentre is at P. If the position vectors A,B,C and P are a,b,c and 4a+b+c respectively, then the position vector of the orthocentre of this triangle, is :
Held on 10 Apr 2016 · Verified 6 Jul 2026.
−(2a+b+c)
a+b+c
2(a+b+c)
0
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