let A, B be non empty compact Subset of (TOP-REAL n); dist_min A,B = dist_min B,A
consider A9, B9 being Subset of (TopSpaceMetr (Euclid n)) such that
A1:
( A = A9 & B = B9 )
and
A2:
dist_min A,B = min_dist_min A9,B9
by Def1;
TopStruct(# the carrier of (TOP-REAL n),the topology of (TOP-REAL n) #) = TopSpaceMetr (Euclid n)
by EUCLID:def 8;
then reconsider A9 = A9, B9 = B9 as non empty compact Subset of (TopSpaceMetr (Euclid n)) by A1, COMPTS_1:33;
dist_min A,B = min_dist_min B9,A9
by A2;
hence
dist_min A,B = dist_min B,A
by A1, Def1; verum