Ror Riemann's zeta function if one proves a relation in the domain $\operatorname{Re}(s)>1$ will this be sufficient proof that it is satisfied in all the z domain
for example if one proves $\zeta(s)=\overline{\zeta\left(\overline s\right)}$ from the original function defined in $\operatorname{Re}(s)>1$ does it require another proof for $\operatorname{Re}(s)<1$ or can we say that it is satisfied for all z domain and why?