reconsider e = ComplexFuncUnit A as Element of (CAlgebra A) ;
take e ; :: according to GROUP_1:def 1 :: thesis: for b1 being Element of the carrier of (CAlgebra A) holds
( b1 * e = b1 & e * b1 = b1 )

thus for b1 being Element of the carrier of (CAlgebra A) holds
( b1 * e = b1 & e * b1 = b1 ) by Lm5; :: thesis: verum