theorem Th35: :: TOPALG_1:35

for X being non empty TopSpace
for a, b, c, d, e being Point of X st a,b are_connected & b,c are_connected & c,d are_connected & d,e are_connected holds
for A being Path of a,b
for B being Path of b,c
for C being Path of c,d
for D being Path of d,e holds (A + (B + C)) + D,(A + B) + (C + D) are_homotopic