Help! I've broken maths! (1 Viewer)

[Ambility]

Ok, here's the deal. I've been trying to graph the function , and on a graphing calculator such as this here, and I've noticed the graph is a circle, with centre and radius . seems to be equivalent to , which is also a circle with centre and radius . Does this suggest that ? I know at the point , it isn't equal to zero.

What's happening with this term?

 

[rand_althor]

Must be something wrong with that graphing calculator. Here's what WolframAlpha shows: http://i.imgur.com/SSPcBxH.png

 

[braintic]

It is a parabola.

The equation can be rearranged to:
(x+2)² + (y-2)² = (x-y)²/2

LHS is the square of the distance of (x,y) from (-2,2).
RHS is the square of the perpendicular distance of (x,y) from the line y=x.

So it is a parabola with focus (-2,2) and directrix y=x.