Lm1:
for X being non empty set
for n1, n2 being Nat st X --> n1 = X --> n2 holds
n1 = n2
theorem
for
b1,
b2 being
bag of 1 holds
b1 + b2 = 1
--> ((b1 . 0) + (b2 . 0))
definition
let n be
Ordinal;
let L be non
degenerated comRing;
func Formal-Series (
n,
L)
-> non
empty strict AlgebraStr over
L means :
Def3:
( ( for
x being
set holds
(
x in the
carrier of
it iff
x is
Series of
n,
L ) ) & ( for
x,
y being
Element of
it for
p,
q being
Series of
n,
L st
x = p &
y = q holds
x + y = p + q ) & ( for
x,
y being
Element of
it for
p,
q being
Series of
n,
L st
x = p &
y = q holds
x * y = p *' q ) & ( for
a being
Element of
L for
x being
Element of
it for
p being
Series of
n,
L st
x = p holds
a * x = a * p ) &
0. it = 0_ (
n,
L) &
1. it = 1_ (
n,
L) );
existence
ex b1 being non empty strict AlgebraStr over L st
( ( for x being set holds
( x in the carrier of b1 iff x is Series of n,L ) ) & ( for x, y being Element of b1
for p, q being Series of n,L st x = p & y = q holds
x + y = p + q ) & ( for x, y being Element of b1
for p, q being Series of n,L st x = p & y = q holds
x * y = p *' q ) & ( for a being Element of L
for x being Element of b1
for p being Series of n,L st x = p holds
a * x = a * p ) & 0. b1 = 0_ (n,L) & 1. b1 = 1_ (n,L) )
uniqueness
for b1, b2 being non empty strict AlgebraStr over L st ( for x being set holds
( x in the carrier of b1 iff x is Series of n,L ) ) & ( for x, y being Element of b1
for p, q being Series of n,L st x = p & y = q holds
x + y = p + q ) & ( for x, y being Element of b1
for p, q being Series of n,L st x = p & y = q holds
x * y = p *' q ) & ( for a being Element of L
for x being Element of b1
for p being Series of n,L st x = p holds
a * x = a * p ) & 0. b1 = 0_ (n,L) & 1. b1 = 1_ (n,L) & ( for x being set holds
( x in the carrier of b2 iff x is Series of n,L ) ) & ( for x, y being Element of b2
for p, q being Series of n,L st x = p & y = q holds
x + y = p + q ) & ( for x, y being Element of b2
for p, q being Series of n,L st x = p & y = q holds
x * y = p *' q ) & ( for a being Element of L
for x being Element of b2
for p being Series of n,L st x = p holds
a * x = a * p ) & 0. b2 = 0_ (n,L) & 1. b2 = 1_ (n,L) holds
b1 = b2
end;
::
deftheorem Def3 defines
Formal-Series POLYALGX:def 3 :
for n being Ordinal
for L being non degenerated comRing
for b3 being non empty strict AlgebraStr over L holds
( b3 = Formal-Series (n,L) iff ( ( for x being set holds
( x in the carrier of b3 iff x is Series of n,L ) ) & ( for x, y being Element of b3
for p, q being Series of n,L st x = p & y = q holds
x + y = p + q ) & ( for x, y being Element of b3
for p, q being Series of n,L st x = p & y = q holds
x * y = p *' q ) & ( for a being Element of L
for x being Element of b3
for p being Series of n,L st x = p holds
a * x = a * p ) & 0. b3 = 0_ (n,L) & 1. b3 = 1_ (n,L) ) );
Lm2:
now for n being Ordinal
for L being non degenerated comRing
for x, e being Element of (Formal-Series (n,L)) st e = 1_ (n,L) holds
( x * e = x & e * x = x )
let n be
Ordinal;
for L being non degenerated comRing
for x, e being Element of (Formal-Series (n,L)) st e = 1_ (n,L) holds
( x * e = x & e * x = x )let L be non
degenerated comRing;
for x, e being Element of (Formal-Series (n,L)) st e = 1_ (n,L) holds
( x * e = x & e * x = x )set F =
Formal-Series (
n,
L);
let x,
e be
Element of
(Formal-Series (n,L));
( e = 1_ (n,L) implies ( x * e = x & e * x = x ) )reconsider a =
x,
b =
e as
Series of
n,
L by Def3;
assume A1:
e = 1_ (
n,
L)
;
( x * e = x & e * x = x )thus x * e =
a *' b
by Def3
.=
x
by A1, POLYNOM1:29
;
e * x = xthus e * x =
b *' a
by Def3
.=
x
by A1, POLYNOM1:30
;
verum
end;
Lm3:
for V being Ring
for V1 being Subring of V holds
( ( for v1, w1 being Element of V1
for v, w being Element of V st v1 = v & w1 = w holds
v1 + w1 = v + w ) & ( for v1, w1 being Element of V1
for v, w being Element of V st v1 = v & w1 = w holds
v1 * w1 = v * w ) & 1_ V1 = 1_ V & 0. V1 = 0. V )
definition
let R be non
degenerated comRing;
existence
ex b1 being Function of (Formal-Series (1,R)),(Formal-Series R) st
for x being object st x in the carrier of (Formal-Series (1,R)) holds
ex x1 being Series of 1,R st
( x1 = x & b1 . x = x1 * NBag1 )
uniqueness
for b1, b2 being Function of (Formal-Series (1,R)),(Formal-Series R) st ( for x being object st x in the carrier of (Formal-Series (1,R)) holds
ex x1 being Series of 1,R st
( x1 = x & b1 . x = x1 * NBag1 ) ) & ( for x being object st x in the carrier of (Formal-Series (1,R)) holds
ex x1 being Series of 1,R st
( x1 = x & b2 . x = x1 * NBag1 ) ) holds
b1 = b2
end;
Lm4:
for R being non degenerated comRing holds
( BSFSeri R is one-to-one & BSFSeri R is onto )
Lm5:
for R being non degenerated comRing holds SBFSeri R is one-to-one
Lm6:
for R being non degenerated comRing holds SBFSeri R is onto
Lm7:
for R being non degenerated comRing holds the carrier of (Polynom-Ring (1,R)) c= the carrier of (Formal-Series (1,R))