let X be non empty set ; for d1, d2 being Element of X
for A being BinOp of X
for M being Function of [:X,X:],X
for V being Algebra
for V1 being Subset of V
for MR being Function of [:REAL ,X:],X st V1 = X & d1 = 0. V & d2 = 1. V & A = the addF of V || V1 & M = the multF of V || V1 & MR = the Mult of V | [:REAL ,V1:] & V1 is having-inverse holds
AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
let d1, d2 be Element of X; for A being BinOp of X
for M being Function of [:X,X:],X
for V being Algebra
for V1 being Subset of V
for MR being Function of [:REAL ,X:],X st V1 = X & d1 = 0. V & d2 = 1. V & A = the addF of V || V1 & M = the multF of V || V1 & MR = the Mult of V | [:REAL ,V1:] & V1 is having-inverse holds
AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
let A be BinOp of X; for M being Function of [:X,X:],X
for V being Algebra
for V1 being Subset of V
for MR being Function of [:REAL ,X:],X st V1 = X & d1 = 0. V & d2 = 1. V & A = the addF of V || V1 & M = the multF of V || V1 & MR = the Mult of V | [:REAL ,V1:] & V1 is having-inverse holds
AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
let M be Function of [:X,X:],X; for V being Algebra
for V1 being Subset of V
for MR being Function of [:REAL ,X:],X st V1 = X & d1 = 0. V & d2 = 1. V & A = the addF of V || V1 & M = the multF of V || V1 & MR = the Mult of V | [:REAL ,V1:] & V1 is having-inverse holds
AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
let V be Algebra; for V1 being Subset of V
for MR being Function of [:REAL ,X:],X st V1 = X & d1 = 0. V & d2 = 1. V & A = the addF of V || V1 & M = the multF of V || V1 & MR = the Mult of V | [:REAL ,V1:] & V1 is having-inverse holds
AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
let V1 be Subset of V; for MR being Function of [:REAL ,X:],X st V1 = X & d1 = 0. V & d2 = 1. V & A = the addF of V || V1 & M = the multF of V || V1 & MR = the Mult of V | [:REAL ,V1:] & V1 is having-inverse holds
AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
let MR be Function of [:REAL ,X:],X; ( V1 = X & d1 = 0. V & d2 = 1. V & A = the addF of V || V1 & M = the multF of V || V1 & MR = the Mult of V | [:REAL ,V1:] & V1 is having-inverse implies AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V )
assume that
A1:
V1 = X
and
A2:
d1 = 0. V
and
A3:
d2 = 1. V
and
A4:
A = the addF of V || V1
and
A5:
M = the multF of V || V1
and
A6:
MR = the Mult of V | [:REAL ,V1:]
and
A7:
for v being Element of V st v in V1 holds
- v in V1
; C0SP1:def 1 AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
reconsider W = AlgebraStr(# X,M,A,MR,d2,d1 #) as non empty AlgebraStr ;
A11:
( W is Abelian & W is add-associative & W is right_zeroed & W is right_complementable & W is commutative & W is associative & W is right_unital & W is right-distributive & W is Algebra-like )
proof
set Mv = the
multF of
V;
set MV = the
Mult of
V;
set Av = the
addF of
V;
thus
W is
right_complementable
( W is commutative & W is associative & W is right_unital & W is right-distributive & W is Algebra-like )
thus
W is
Algebra-like
verumproof
let x,
y,
z be
Element of
W;
FUNCSDOM:def 20 for b1, b2 being Element of REAL holds
( b1 * (x * y) = (b1 * x) * y & b1 * (x + y) = (b1 * x) + (b1 * y) & (b1 + b2) * x = (b1 * x) + (b2 * x) & (b1 * b2) * x = b1 * (b2 * x) )
reconsider x1 =
x,
y1 =
y as
Element of
V by A1, TARSKI:def 3;
let a,
b be
Real;
( a * (x * y) = (a * x) * y & a * (x + y) = (a * x) + (a * y) & (a + b) * x = (a * x) + (b * x) & (a * b) * x = a * (b * x) )
A16:
a * x = a * x1
by A10;
x * y = x1 * y1
by A9;
then
a * (x * y) = a * (x1 * y1)
by A10;
then
a * (x * y) = (a * x1) * y1
by FUNCSDOM:def 20;
hence
a * (x * y) = (a * x) * y
by A9, A16;
( a * (x + y) = (a * x) + (a * y) & (a + b) * x = (a * x) + (b * x) & (a * b) * x = a * (b * x) )
x + y = x1 + y1
by A8;
then
a * (x + y) = a * (x1 + y1)
by A10;
then A17:
a * (x + y) = (a * x1) + (a * y1)
by FUNCSDOM:def 20;
a * y = a * y1
by A10;
hence
a * (x + y) = (a * x) + (a * y)
by A8, A16, A17;
( (a + b) * x = (a * x) + (b * x) & (a * b) * x = a * (b * x) )
A18:
b * x = b * x1
by A10;
(a + b) * x = (a + b) * x1
by A10;
then
(a + b) * x = (a * x1) + (b * x1)
by FUNCSDOM:def 20;
hence
(a + b) * x = (a * x) + (b * x)
by A8, A16, A18;
(a * b) * x = a * (b * x)
(a * b) * x = (a * b) * x1
by A10;
then
(a * b) * x = a * (b * x1)
by FUNCSDOM:def 20;
hence
(a * b) * x = a * (b * x)
by A10, A18;
verum
end;
end;
( 0. W = 0. V & 1. W = 1. V )
by A2, A3;
hence
AlgebraStr(# X,M,A,MR,d2,d1 #) is Subalgebra of V
by A1, A4, A5, A6, A11, Def9; verum