Even and odd functions

Determine if the following functions are even or odd:

$f (x) = 1$
$f (x) = x$
$f (x) = x^2$

The function is pair.
Let's see that the function is odd:

$$f (x) =-f (-x)$$

$$x = - (-x)$$

Let's verify that the function is pair:

$$f (x) = f (-x)$$

$$x^2=(-x)^2=x^2$$

Even.
Odd.
Even.