24/04/28 08:53:07.89 pfxD2O3Q.net
>>602
Wolfram言語による解
Clear[fn]
n=7
fn[a_] := (
p=Table[Cos[t*2Pi/n]+I*Sin[t*2Pi/n],{t,n+1}];
t0=2Pi/n;
t2i[t_] := (
i=Mod[Floor[t/t0],n];
j=i+1;
i=If[i!=0,i,n];
line1={{0,0},{Cos[t],Sin[t]}};
line2={{Re[p[[i]]],Im[p[[i]]]},{Re[p[[j]]],Im[p[[j]]]}};
ResourceFunction["LineIntersection"][line1,line2]
);
ABC=Map[t2i,{a,a+2Pi/3,a+2Pi/3+2Pi/3}];
AB=EuclideanDistance[ABC[[1]],ABC[[2]]];
BC=EuclideanDistance[ABC[[2]],ABC[[3]]];
CA=EuclideanDistance[ABC[[3]],ABC[[1]]];
(AB-BC)^2+(BC-CA)^2+(CA-AB)^2)
Minimize[{fn,0<a && a<2Pi/n},a]