1. The problem statement, all variables and given/known data If a function satisfies f(x+1)+f(x-1)=√2.f(x), the the period of f(x)=_____ 2. Relevant equations none 3. The attempt at a solution I first tried to get rid of the irrational term. f(x+2)+f(x)= √2.f(x+1) f(x)+f(x-2) = √2.f(x-1) adding the above equation, and substituting the given equation, f(x+2)+f(x-2)+2f(x)=√2.(√2.f(x))=2f(x) f(x+2)+f(x-2)=0 f(x+4)+f(x)=0 Now instead of getting f(a-x)=f(x) equation, i am getting f(a-x)=-f(x). How can I find its period?