In a circle with a radius R a convex hexagon is inscribed. The diagonals AD and BE,BE and CF,CF and AD of the hexagon intersect at the points M,N andK, respectively. Let r1,r2,r3,r4,r5,r6 be the radii of circles inscribed in triangles ABM,BCN,CDK,DEM,EFN,AFK respectively. Prove that.r1+r2+r3+r4+r5+r6≤R3 . geometryinequalitiesgeometric inequality