set E = EqRel R,I;
let X, Y be strict doubleLoopStr ; :: thesis: ( the carrier of X = Class (EqRel R,I) & 1. X = Class (EqRel R,I),(1. R) & 0. X = Class (EqRel R,I),(0. R) & ( for x, y being Element of X ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the addF of X . x,y = Class (EqRel R,I),(a + b) ) ) & ( for x, y being Element of X ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the multF of X . x,y = Class (EqRel R,I),(a * b) ) ) & the carrier of Y = Class (EqRel R,I) & 1. Y = Class (EqRel R,I),(1. R) & 0. Y = Class (EqRel R,I),(0. R) & ( for x, y being Element of Y ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the addF of Y . x,y = Class (EqRel R,I),(a + b) ) ) & ( for x, y being Element of Y ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the multF of Y . x,y = Class (EqRel R,I),(a * b) ) ) implies X = Y )

assume that
A13: the carrier of X = Class (EqRel R,I) and
A14: ( 1. X = Class (EqRel R,I),(1. R) & 0. X = Class (EqRel R,I),(0. R) ) and
A15: for x, y being Element of X ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the addF of X . x,y = Class (EqRel R,I),(a + b) ) and
A16: for x, y being Element of X ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the multF of X . x,y = Class (EqRel R,I),(a * b) ) and
A17: the carrier of Y = Class (EqRel R,I) and
A18: ( 1. Y = Class (EqRel R,I),(1. R) & 0. Y = Class (EqRel R,I),(0. R) ) and
A19: for x, y being Element of Y ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the addF of Y . x,y = Class (EqRel R,I),(a + b) ) and
A20: for x, y being Element of Y ex a, b being Element of R st
( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b & the multF of Y . x,y = Class (EqRel R,I),(a * b) ) ; :: thesis: X = Y
A21: for x, y being Element of X holds the multF of X . x,y = the multF of Y . x,y
proof
let x, y be Element of X; :: thesis: the multF of X . x,y = the multF of Y . x,y
consider a, b being Element of R such that
A22: x = Class (EqRel R,I),a and
A23: y = Class (EqRel R,I),b and
A24: the multF of X . x,y = Class (EqRel R,I),(a * b) by A16;
consider a1, b1 being Element of R such that
A25: x = Class (EqRel R,I),a1 and
A26: y = Class (EqRel R,I),b1 and
A27: the multF of Y . x,y = Class (EqRel R,I),(a1 * b1) by A13, A17, A20;
b - b1 in I by A23, A26, Th6;
then A28: a1 * (b - b1) in I by IDEAL_1:def 2;
A29: ((a - a1) * b) + (a1 * (b - b1)) = ((a * b) - (a1 * b)) + (a1 * (b - b1)) by VECTSP_1:45
.= ((a * b) - (a1 * b)) + ((a1 * b) - (a1 * b1)) by VECTSP_1:43
.= (((a * b) - (a1 * b)) + (a1 * b)) - (a1 * b1) by RLVECT_1:42
.= (a * b) - (a1 * b1) by Th1 ;
a - a1 in I by A22, A25, Th6;
then (a - a1) * b in I by IDEAL_1:def 3;
then ((a - a1) * b) + (a1 * (b - b1)) in I by A28, IDEAL_1:def 1;
hence the multF of X . x,y = the multF of Y . x,y by A24, A27, A29, Th6; :: thesis: verum
end;
for x, y being Element of X holds the addF of X . x,y = the addF of Y . x,y
proof
let x, y be Element of X; :: thesis: the addF of X . x,y = the addF of Y . x,y
consider a, b being Element of R such that
A30: ( x = Class (EqRel R,I),a & y = Class (EqRel R,I),b ) and
A31: the addF of X . x,y = Class (EqRel R,I),(a + b) by A15;
consider a1, b1 being Element of R such that
A32: ( x = Class (EqRel R,I),a1 & y = Class (EqRel R,I),b1 ) and
A33: the addF of Y . x,y = Class (EqRel R,I),(a1 + b1) by A13, A17, A19;
( a - a1 in I & b - b1 in I ) by A30, A32, Th6;
then A34: (a - a1) + (b - b1) in I by IDEAL_1:def 1;
(a + b) - (a1 + b1) = ((a + b) - a1) - b1 by RLVECT_1:41
.= ((a - a1) + b) - b1 by RLVECT_1:42
.= (a - a1) + (b - b1) by RLVECT_1:42 ;
hence the addF of X . x,y = the addF of Y . x,y by A31, A33, A34, Th6; :: thesis: verum
end;
then the addF of X = the addF of Y by A13, A17, BINOP_1:2;
hence X = Y by A13, A14, A17, A18, A21, BINOP_1:2; :: thesis: verum