let l be RLSStruct ; ( RLSStruct(# the carrier of l, the ZeroF of l, the addF of l, the Mult of l #) is RealLinearSpace implies l is RealLinearSpace )
assume A1:
RLSStruct(# the carrier of l, the ZeroF of l, the addF of l, the Mult of l #) is RealLinearSpace
; l is RealLinearSpace
reconsider l = l as non empty RLSStruct by A1;
reconsider l0 = RLSStruct(# the carrier of l,(0. l), the addF of l, the Mult of l #) as RealLinearSpace by A1;
A2:
l is Abelian
A3:
l is right_zeroed
A4:
l is right_complementable
A6:
for v being VECTOR of l holds 1 * v = v
A7:
for a, b being Real
for v being VECTOR of l holds (a * b) * v = a * (b * v)
A8:
for a, b being Real
for v being VECTOR of l holds (a + b) * v = (a * v) + (b * v)
A9:
for a being Real
for v, w being VECTOR of l holds a * (v + w) = (a * v) + (a * w)
l is add-associative
hence
l is RealLinearSpace
by A2, A3, A4, A9, A8, A7, A6, RLVECT_1:def 5, RLVECT_1:def 6, RLVECT_1:def 7, RLVECT_1:def 8; verum