#### Fill Question

If y=f(x) is an even function in its domain R, then f(1+\sqrt{2})-f(\dfrac{1}{1-\sqrt{2}})=

If y=f(x) is an even function in its domain R, then f(1+\sqrt{2})-f(\dfrac{1}{1-\sqrt{2}})=

Since f(x) is an even function, f(x)=f(-x)

f(\dfrac{1}{1-\sqrt{2}})=f(-(1+\sqrt{2})=f(1+\sqrt{2} )

Therefore,

f(1+\sqrt{2})- f(\dfrac{1}{1-\sqrt{2}})=0