let V be RealUnitarySpace; ( ((0). V) + ((Omega). V) = UNITSTR(# the carrier of V, the ZeroF of V, the U7 of V, the Mult of V, the scalar of V #) & ((Omega). V) + ((0). V) = UNITSTR(# the carrier of V, the ZeroF of V, the U7 of V, the Mult of V, the scalar of V #) )
thus ((0). V) + ((Omega). V) =
(Omega). V
by Th9
.=
UNITSTR(# the carrier of V, the ZeroF of V, the U7 of V, the Mult of V, the scalar of V #)
by RUSUB_1:def 3
; ((Omega). V) + ((0). V) = UNITSTR(# the carrier of V, the ZeroF of V, the U7 of V, the Mult of V, the scalar of V #)
hence
((Omega). V) + ((0). V) = UNITSTR(# the carrier of V, the ZeroF of V, the U7 of V, the Mult of V, the scalar of V #)
by Lm1; verum