Here's the graph of  in red.



Notice that it is NOT symmetrical with respect to the y-axis.

Now here's the graph of  in green:



Notice that it IS symmetrical with respect to the y-axis,
and has a sharp point at the bottom.

Notice how they look if we put them on the same set of 
coordinate axes:



They coincide exactly on the right of the origin where x is positive,
but on the left of the origin where x is negative the second (green)
graph is the red graph shifted one unit right.

Edwin