set f = canHom_Z/ (p,F);
hereby :: according to VECTSP_1:def 19 :: thesis: canHom_Z/ (p,F) is multiplicative
let x, y be Element of (Z/ p); :: thesis: ((canHom_Z/ (p,F)) . x) + ((canHom_Z/ (p,F)) . y) = (canHom_Z/ (p,F)) . (x + y)
reconsider x1 = x, y1 = y as Element of INT.Ring by ORDINAL1:def 12, NUMBERS:17;
A1: x + y = (x1 + y1) mod p by GR_CY_1:def 4;
reconsider z = (x1 + y1) mod p as Element of INT.Ring by INT_1:def 2;
thus ((canHom_Z/ (p,F)) . x) + ((canHom_Z/ (p,F)) . y) = (x1 '*' (1. F)) + ((canHom_Z/ (p,F)) . y) by Lm14
.= (x1 '*' (1. F)) + (y1 '*' (1. F)) by Lm14
.= (x1 + y1) '*' (1. F) by Th61
.= z '*' (1. F) by Th104
.= (canHom_Z/ (p,F)) . (x + y) by Lm14, A1 ; :: thesis: verum
end;
hereby :: according to GROUP_6:def 6 :: thesis: verum
let x, y be Element of (Z/ p); :: thesis: ((canHom_Z/ (p,F)) . x) * ((canHom_Z/ (p,F)) . y) = (canHom_Z/ (p,F)) . (x * y)
reconsider x1 = x, y1 = y as Element of INT.Ring by ORDINAL1:def 12, NUMBERS:17;
A2: x * y = (x1 * y1) mod p by INT_3:def 10;
reconsider z = (x1 * y1) mod p as Element of INT.Ring by INT_1:def 2;
thus ((canHom_Z/ (p,F)) . x) * ((canHom_Z/ (p,F)) . y) = (x1 '*' (1. F)) * ((canHom_Z/ (p,F)) . y) by Lm14
.= (x1 '*' (1. F)) * (y1 '*' (1. F)) by Lm14
.= (x1 * y1) '*' (1. F) by Th66
.= z '*' (1. F) by Th104
.= (canHom_Z/ (p,F)) . (x * y) by Lm14, A2 ; :: thesis: verum
end;