let D be non empty set ; :: thesis: for e being Element of D
for F, G being BinOp of D st F is associative & F is having_a_unity & F is having_an_inverseOp & G is_distributive_wrt F & e = the_unity_wrt F holds
for d being Element of D holds
( G . e,d = e & G . d,e = e )
let e be Element of D; :: thesis: for F, G being BinOp of D st F is associative & F is having_a_unity & F is having_an_inverseOp & G is_distributive_wrt F & e = the_unity_wrt F holds
for d being Element of D holds
( G . e,d = e & G . d,e = e )
let F, G be BinOp of D; :: thesis: ( F is associative & F is having_a_unity & F is having_an_inverseOp & G is_distributive_wrt F & e = the_unity_wrt F implies for d being Element of D holds
( G . e,d = e & G . d,e = e ) )
assume that
A1:
F is associative
and
A2:
F is having_a_unity
and
A3:
F is having_an_inverseOp
and
A4:
G is_distributive_wrt F
and
A5:
e = the_unity_wrt F
; :: thesis: for d being Element of D holds
( G . e,d = e & G . d,e = e )
let d be Element of D; :: thesis: ( G . e,d = e & G . d,e = e )
set ed = G . e,d;
F . (G . e,d),(G . e,d) =
G . (F . e,e),d
by A4, BINOP_1:23
.=
G . e,d
by A2, A5, SETWISEO:23
;
hence
G . e,d = e
by A1, A2, A3, A5, Th69; :: thesis: G . d,e = e
set de = G . d,e;
F . (G . d,e),(G . d,e) =
G . d,(F . e,e)
by A4, BINOP_1:23
.=
G . d,e
by A2, A5, SETWISEO:23
;
hence
G . d,e = e
by A1, A2, A3, A5, Th69; :: thesis: verum