let D be non empty set ; :: thesis: for d1, d2 being Element of D
for g being BinOp of D holds g "**" <*d1,d2*> = g . d1,d2
let d1, d2 be Element of D; :: thesis: for g being BinOp of D holds g "**" <*d1,d2*> = g . d1,d2
let g be BinOp of D; :: thesis: g "**" <*d1,d2*> = g . d1,d2
A1:
( len <*d1*> = 1 & len <*d2*> = 1 )
by FINSEQ_1:56;
thus g "**" <*d1,d2*> =
g "**" (<*d1*> ^ <*d2*>)
by FINSEQ_1:def 9
.=
g . (g "**" <*d1*>),d2
by A1, Th5
.=
g . d1,d2
by Lm4
; :: thesis: verum