let K be non empty right_complementable Abelian add-associative right_zeroed well-unital distributive associative doubleLoopStr ; for V being VectSp of K
for W being Subspace of V
for A being Vector of (VectQuot (V,W))
for v being Vector of V
for a being Scalar of st A = v + W holds
a * A = (a * v) + W
let V be VectSp of K; for W being Subspace of V
for A being Vector of (VectQuot (V,W))
for v being Vector of V
for a being Scalar of st A = v + W holds
a * A = (a * v) + W
let W be Subspace of V; for A being Vector of (VectQuot (V,W))
for v being Vector of V
for a being Scalar of st A = v + W holds
a * A = (a * v) + W
set vw = VectQuot (V,W);
set lm = the lmult of (VectQuot (V,W));
let A be Vector of (VectQuot (V,W)); for v being Vector of V
for a being Scalar of st A = v + W holds
a * A = (a * v) + W
let v be Vector of V; for a being Scalar of st A = v + W holds
a * A = (a * v) + W
let a be Scalar of ; ( A = v + W implies a * A = (a * v) + W )
assume A1:
A = v + W
; a * A = (a * v) + W
A is Coset of W
by Th22;
then
A in { B where B is Coset of W : verum }
;
then reconsider w = A as Element of CosetSet (V,W) ;
thus a * A =
the lmult of (VectQuot (V,W)) . (a,A)
.=
(lmultCoset (V,W)) . (a,w)
by Def6
.=
(a * v) + W
by A1, Def5
; verum