let a, b be real number ; ( a <= b implies for x, y being Point of (Closed-Interval-TSpace a,b)
for P, Q being Path of x,y holds P,Q are_homotopic )
assume A1:
a <= b
; for x, y being Point of (Closed-Interval-TSpace a,b)
for P, Q being Path of x,y holds P,Q are_homotopic
let x, y be Point of (Closed-Interval-TSpace a,b); for P, Q being Path of x,y holds P,Q are_homotopic
let P, Q be Path of x,y; P,Q are_homotopic
Closed-Interval-TSpace a,b is interval
by A1, Th13;
hence
P,Q are_homotopic
by Th16; verum