Let ABC be an equilateral triangle with orthocenter at the origin and the side BC on the line x+22y=4. If the co-ordinates of the vertex A are ( α,β ), then the greatest integer less than or equal to ∣α+2β∣ is
Answer: 4
Solution
For an equilateral triangle the orthocentre coincides with the centroid, so the centroid is the origin. The perpendicular distance from the origin to BC:x+22y=4 is 1+84=34. The centroid divides the median from A in the ratio 2:1, so the distance from the centroid to A is 2×34=38, measured along the normal to BC and on the side opposite to BC. The unit normal is 3(1,22), and moving away from the line gives A=−38⋅3(1,22)=(−98,−9162). Then α+2β=−98−932=−940, so ∣α+2β∣=940≈4.44 and the greatest integer not exceeding it is 4.
JEE Main · 2026 · 28 Jan 2026 · Shift 1 · Integer answer