
Distance from origin to line x+y=3 is inradius.
r=OM=23
&\mathrm{sin}30^{\circ}=\frac{1}{2}=\frac{r}{R}\Rightarrow R=\frac{6}{\sqrt{2}}
∴r+R=29
JEE Main 2021 — Mathematics Coordinate Geometry
Let the centroid of an equilateral triangle ABC be at the origin. Let one of the sides of the equilateral triangle be along the straight line x+y=3. If R and r be the radius of circumcircle and incircle respectively of ΔABC, then (R+r) is equal to :
Held on 18 Mar 2021 · Verified 6 Jul 2026.
29
72
22
32
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