A conic section is a curve in ℝ² that can be described by an equation of the form f(x, y) = c₁ + c₂x + c₃y + c₄x² + c₅xy + c₆y² = 0, where at least one of the coefficients cₖ is non
a) Circle
b) Parabola
c) Ellipse
d) Hyperbola