let L be Z_Lattice; for v being Vector of (DivisibleMod L) holds
( (ScProductDM L) . ((0. (DivisibleMod L)),v) = 0 & (ScProductDM L) . (v,(0. (DivisibleMod L))) = 0 )
let v be Vector of (DivisibleMod L); ( (ScProductDM L) . ((0. (DivisibleMod L)),v) = 0 & (ScProductDM L) . (v,(0. (DivisibleMod L))) = 0 )
thus A1: (ScProductDM L) . ((0. (DivisibleMod L)),v) =
(ScProductDM L) . ((v - v),v)
by RLVECT_1:15
.=
((ScProductDM L) . (v,v)) + ((ScProductDM L) . ((- v),v))
by ThSPDM1
.=
((ScProductDM L) . (v,v)) - ((ScProductDM L) . (v,v))
by ThScDM1
.=
0
; (ScProductDM L) . (v,(0. (DivisibleMod L))) = 0
thus
(ScProductDM L) . (v,(0. (DivisibleMod L))) = 0
by A1, ThSPDM1; verum