let F be ext-real-membered set ; :: thesis: for f being ExtReal
for e being set st e in F /// f holds
ex w being Element of ExtREAL st
( e = w / f & w in F )

let f be ExtReal; :: thesis: for e being set st e in F /// f holds
ex w being Element of ExtREAL st
( e = w / f & w in F )

let e be set ; :: thesis: ( e in F /// f implies ex w being Element of ExtREAL st
( e = w / f & w in F ) )

F /// f = { (w / f) where w is Element of ExtREAL : w in F } by Th224;
hence ( e in F /// f implies ex w being Element of ExtREAL st
( e = w / f & w in F ) ) ; :: thesis: verum