let V be Z_Module; for z being Element of V
for i, n being Element of INT.Ring st i <> 0. INT.Ring & n <> 0. INT.Ring & V is Mult-cancelable holds
Class ((EQRZM V),[z,i]) = Class ((EQRZM V),[(n * z),(n * i)])
let z be Element of V; for i, n being Element of INT.Ring st i <> 0. INT.Ring & n <> 0. INT.Ring & V is Mult-cancelable holds
Class ((EQRZM V),[z,i]) = Class ((EQRZM V),[(n * z),(n * i)])
let i, n be Element of INT.Ring; ( i <> 0. INT.Ring & n <> 0. INT.Ring & V is Mult-cancelable implies Class ((EQRZM V),[z,i]) = Class ((EQRZM V),[(n * z),(n * i)]) )
assume AS:
( i <> 0. INT.Ring & n <> 0. INT.Ring & V is Mult-cancelable )
; Class ((EQRZM V),[z,i]) = Class ((EQRZM V),[(n * z),(n * i)])
then B61:
not i in {0}
by TARSKI:def 1;
i in INT \ {0}
by XBOOLE_0:def 5, B61;
then X1:
[z,i] in [: the carrier of V,(INT \ {0}):]
by ZFMISC_1:87;
(n * i) * z =
(i * n) * z
.=
i * (n * z)
by VECTSP_1:def 16
;
then
[[z,i],[(n * z),(n * i)]] in EQRZM V
by AS, LMEQR001;
hence
Class ((EQRZM V),[z,i]) = Class ((EQRZM V),[(n * z),(n * i)])
by X1, EQREL_1:35; verum