let S, T be non empty TopSpace; for s being Point of S
for f being continuous Function of S,T
for ls being Loop of s holds (FundGrIso f,s) . (Class (EqRel S,s),ls) = Class (EqRel T,(f . s)),(f * ls)
let s be Point of S; for f being continuous Function of S,T
for ls being Loop of s holds (FundGrIso f,s) . (Class (EqRel S,s),ls) = Class (EqRel T,(f . s)),(f * ls)
let f be continuous Function of S,T; for ls being Loop of s holds (FundGrIso f,s) . (Class (EqRel S,s),ls) = Class (EqRel T,(f . s)),(f * ls)
let ls be Loop of s; (FundGrIso f,s) . (Class (EqRel S,s),ls) = Class (EqRel T,(f . s)),(f * ls)
reconsider x = Class (EqRel S,s),ls as Element of (pi_1 S,s) by TOPALG_1:48;
consider ls1 being Loop of s such that
A1:
x = Class (EqRel S,s),ls1
and
A2:
(FundGrIso f,s) . x = Class (EqRel T,(f . s)),(f * ls1)
by Def1;
ls,ls1 are_homotopic
by A1, TOPALG_1:47;
then
f * ls,f * ls1 are_homotopic
by Th28;
hence
(FundGrIso f,s) . (Class (EqRel S,s),ls) = Class (EqRel T,(f . s)),(f * ls)
by A2, TOPALG_1:47; verum