let R be Ring; for G1, G2, G3 being LeftMod of R
for G being Morphism of G2,G3
for F being Morphism of G1,G2 holds G * F is strict Morphism of G1,G3
let G1, G2, G3 be LeftMod of R; for G being Morphism of G2,G3
for F being Morphism of G1,G2 holds G * F is strict Morphism of G1,G3
let G be Morphism of G2,G3; for F being Morphism of G1,G2 holds G * F is strict Morphism of G1,G3
let F be Morphism of G1,G2; G * F is strict Morphism of G1,G3
consider g being Function of G2,G3 such that
A1:
LModMorphismStr(# the Dom of G, the Cod of G, the Fun of G #) = LModMorphismStr(# G2,G3,g #)
and
( g is additive & g is homogeneous )
by Th7;
consider f being Function of G1,G2 such that
A2:
LModMorphismStr(# the Dom of F, the Cod of F, the Fun of F #) = LModMorphismStr(# G1,G2,f #)
and
( f is additive & f is homogeneous )
by Th7;
dom G =
G2
by Def8
.=
cod F
by Def8
;
then
G * F = LModMorphismStr(# G1,G3,(g * f) #)
by A1, A2, Def10;
then
( dom (G * F) = G1 & cod (G * F) = G3 )
;
hence
G * F is strict Morphism of G1,G3
by Def8; verum