Answer
Even.
Work Step by Step
To find $f(-x)$, replace $x$ with $-x$ to get $f(-x)=\frac{1}{(-x)^2}=-\frac{1}{(-1)^2x^2}=\frac{1}{x^2}$. Since $f(x)=\frac{1}{x^2}$, $f(x)=f(-x)$. Therefore, by the definition of an even function, this function is even.
