Refrection of a function across the y-axis, changes the sign of x in the function.
Thus, given the function:

Refrection of the function across the y-axis will result in the function:

Refrecting a function across the x-axis, changes the sign of the function.
Thus, refrecting the function:

across the x-axis will result in the function:

The graph of

and

is attached.
The green curve represents the graph of the function

, while the orange curve represents the graph of the function

.