let z2, z1 be Element of F_Complex ; :: thesis: ( z2 <> 0. F_Complex & z1 / z2 = 0. F_Complex implies z1 = 0. F_Complex )
reconsider z19 = z1, z29 = z2 as Element of COMPLEX by Def1;
assume A1: z2 <> 0. F_Complex ; :: thesis: ( not z1 / z2 = 0. F_Complex or z1 = 0. F_Complex )
assume z1 / z2 = 0. F_Complex ; :: thesis: z1 = 0. F_Complex
then z19 / z29 = 0. F_Complex by A1, Th8;
hence z1 = 0. F_Complex by A1, Th9; :: thesis: verum