thus R_Quaternion is add-associative by Th2; :: thesis: ( R_Quaternion is right_zeroed & R_Quaternion is right_complementable & R_Quaternion is Abelian & R_Quaternion is associative & R_Quaternion is left_unital & R_Quaternion is right_unital & R_Quaternion is distributive & R_Quaternion is almost_right_invertible & not R_Quaternion is degenerated )
thus R_Quaternion is right_zeroed :: thesis: ( R_Quaternion is right_complementable & R_Quaternion is Abelian & R_Quaternion is associative & R_Quaternion is left_unital & R_Quaternion is right_unital & R_Quaternion is distributive & R_Quaternion is almost_right_invertible & not R_Quaternion is degenerated )
proof
let x be Element of R_Quaternion; :: according to RLVECT_1:def 4 :: thesis: x + (0. R_Quaternion) = x
reconsider x1 = x as Element of QUATERNION by Def10;
thus x + (0. R_Quaternion) = the addF of R_Quaternion . (x1,0q) by Def10
.= addquaternion . (x1,0q) by Def10
.= x1 + 0q by Def4
.= x by Th3 ; :: thesis: verum
end;
thus R_Quaternion is right_complementable :: thesis: ( R_Quaternion is Abelian & R_Quaternion is associative & R_Quaternion is left_unital & R_Quaternion is right_unital & R_Quaternion is distributive & R_Quaternion is almost_right_invertible & not R_Quaternion is degenerated )
proof
let x be Element of R_Quaternion; :: according to ALGSTR_0:def 16 :: thesis: x is right_complementable
reconsider x1 = x as Element of QUATERNION by Def10;
reconsider y = - x1 as Element of R_Quaternion by Def10;
take y ; :: according to ALGSTR_0:def 11 :: thesis: x + y = 0. R_Quaternion
thus x + y = 0. R_Quaternion by Th39, QUATERNI:def 8; :: thesis: verum
end;
thus R_Quaternion is Abelian ; :: thesis: ( R_Quaternion is associative & R_Quaternion is left_unital & R_Quaternion is right_unital & R_Quaternion is distributive & R_Quaternion is almost_right_invertible & not R_Quaternion is degenerated )
thus R_Quaternion is associative by Th16; :: thesis: ( R_Quaternion is left_unital & R_Quaternion is right_unital & R_Quaternion is distributive & R_Quaternion is almost_right_invertible & not R_Quaternion is degenerated )
thus ( R_Quaternion is left_unital & R_Quaternion is right_unital ) ; :: thesis: ( R_Quaternion is distributive & R_Quaternion is almost_right_invertible & not R_Quaternion is degenerated )
thus R_Quaternion is distributive by Th17, Th18; :: thesis: ( R_Quaternion is almost_right_invertible & not R_Quaternion is degenerated )
thus R_Quaternion is almost_right_invertible :: thesis: not R_Quaternion is degenerated
proof
let x be Element of R_Quaternion; :: according to ALGSTR_0:def 39 :: thesis: ( x = 0. R_Quaternion or x is right_invertible )
assume A1: x <> 0. R_Quaternion ; :: thesis: x is right_invertible
reconsider x1 = x as Element of QUATERNION by Def10;
reconsider y = x1 " as Element of R_Quaternion by Def10;
take y ; :: according to ALGSTR_0:def 28 :: thesis: x * y = 1. R_Quaternion
x1 <> 0q by A1, Def10;
then x * y = 1 by Th31
.= 1. R_Quaternion by Def10 ;
hence x * y = 1. R_Quaternion ; :: thesis: verum
end;
1. R_Quaternion = 1q by Def10;
then 0. R_Quaternion <> 1. R_Quaternion by Def10;
hence not R_Quaternion is degenerated ; :: thesis: verum