Re: HSC 2014 4U Marathon
This can fall under graphs
\\ $An implicit curve is sketched in the$ \ xy \ $plane with the equation$ \\ \\ Ax^2 + By^2 + Cxy + D = 0 \ \ \ \ \ $With$ \ \ A,B,C,D > 0 \\ \\ $Show that in order for the curve to be an ellipse then$ \ \ \ \ C^2 \geq 4AB