let F be Field; for a, b being Element of F
for c being Element of NonZero F holds (omf F) . a,((ovf F) . b,c) = (ovf F) . ((omf F) . a,b),c
let a, b be Element of F; for c being Element of NonZero F holds (omf F) . a,((ovf F) . b,c) = (ovf F) . ((omf F) . a,b),c
let c be Element of NonZero F; (omf F) . a,((ovf F) . b,c) = (ovf F) . ((omf F) . a,b),c
reconsider revfc = (revf F) . c as Element of F by XBOOLE_0:def 5;
thus (omf F) . a,((ovf F) . b,c) =
a * (b * revfc)
by Def2
.=
(a * b) * revfc
by REALSET2:23
.=
(ovf F) . ((omf F) . a,b),c
by Def2
; verum