let FT be non empty RelStr ; for A being Subset of FT
for x being Element of FT st x in A holds
<*x*> is_minimum_path_in A,x,x
let A be Subset of FT; for x being Element of FT st x in A holds
<*x*> is_minimum_path_in A,x,x
let x be Element of FT; ( x in A implies <*x*> is_minimum_path_in A,x,x )
assume A1:
x in A
; <*x*> is_minimum_path_in A,x,x
thus
<*x*> is continuous
; FINTOPO6:def 8 ( rng <*x*> c= A & <*x*> . 1 = x & <*x*> . (len <*x*>) = x & ( for h being FinSequence of FT st h is continuous & rng h c= A & h . 1 = x & h . (len h) = x holds
len <*x*> <= len h ) )
{x} c= A
by A1, ZFMISC_1:31;
hence
rng <*x*> c= A
by FINSEQ_1:38; ( <*x*> . 1 = x & <*x*> . (len <*x*>) = x & ( for h being FinSequence of FT st h is continuous & rng h c= A & h . 1 = x & h . (len h) = x holds
len <*x*> <= len h ) )
len <*x*> = 1
by FINSEQ_1:40;
hence
( <*x*> . 1 = x & <*x*> . (len <*x*>) = x & ( for h being FinSequence of FT st h is continuous & rng h c= A & h . 1 = x & h . (len h) = x holds
len <*x*> <= len h ) )
by Def6, FINSEQ_1:40; verum