import trembling; startTrembling(); size(12cm,0); point A=(0,0), B=(5,2), C=(3,4); triangle t=triangle(A,B,C), et1=triangle(A,B,rotate(-60,A)*B), et2=triangle(B,C,rotate(-60,B)*C), et3=triangle(C,A,rotate(-60,C)*A); draw(et1^^et2^^et3, 0.8*red); dot(et1.Path()^^et2.Path()^^et3.Path()); draw(t); label(t, alignFactor=2.5); point[] F=fermat(t); dot("$F_1$",F[0], S, red); dot("$F_2$",F[1], W, purple); draw(circle(et1)^^circle(et2)^^circle(et3), 0.8*green); draw(line(C,et1.C)^^line(A,et2.C)^^line(B,et3.C), 0.8*blue); label("$N_1$",et1.VC); label("$N_2$",et2.VC); label("$N_3$",et3.VC);