A quadratic graph is produced when you have an equation of the form y = a x 2 + b x + c, where b and c can be zero but a cannot be zero. All quadratic graphs have a line of symmetry.

Nature Physics - Going randomNow, Josh Izaac et al. show that this needn't be the case: by taking advantage of parity–time (PT)-symmetry, which emerges in non-Hermitian systems with gain and ...

All quadratic graphs have a line of symmetry. Positive quadratic graphs (where \ (a > 0\)) are U-shaped and have a turning point at the bottom of the curve.