let X be ComplexUnitarySpace; for x being Point of X
for r being Real holds Ball x,r c= cl_Ball x,r
let x be Point of X; for r being Real holds Ball x,r c= cl_Ball x,r
let r be Real; Ball x,r c= cl_Ball x,r
for y being Point of X st y in Ball x,r holds
y in cl_Ball x,r
by Th50;
hence
Ball x,r c= cl_Ball x,r
by SUBSET_1:7; verum