Parabola

Parabolic compass designed by Leonardo da Vinci

Cone with cross-sections (To enlarge, click on diagram. To shrink, go to previous page.)

A parabolic segment can be constructed exactly from a quadratic Bézier curve: tangents to the parabola at the curve's end points intersect at its control point

A parabola (/pəˈræbələ/; plural parabolas or parabolae, adjective parabolic, from Greek:παραβολή) is a two-dimensional, mirror-symmetrical curve, which is approximately U-shaped when oriented as shown in the diagram below, but which can be in any orientation in its plane. It fits any of several superficially different mathematical descriptions which can all be proved to define curves of exactly the same shape.

单词	Parabolic curve
释义	Parabolic curve 英语百科 Parabola A parabola (/pəˈræbələ/; plural parabolas or parabolae, adjective parabolic, from Greek:παραβολή) is a two-dimensional, mirror-symmetrical curve, which is approximately U-shaped when oriented as shown in the diagram below, but which can be in any orientation in its plane. It fits any of several superficially different mathematical descriptions which can all be proved to define curves of exactly the same shape.
随便看	pericardial, pericardiac pericardial pleura Pericardial pneumatosis Pericardial pneumohematosis pericardial pressure pericardial pseudocirrhosis of liver pericardial pseudocirrhosis of the liver pericardial pyopneumatosis pericardial region Pericardial rub Pericardial sac pericardial sac drainage pericardial sacs pericardial septum pericardial serum Pericardial sinus Pericardial space pericardial spaces pericardial splash pericardial splenosis pericardial stripping Pericardial tamponade pericardial thickening pericardial thickening and calaification pericardial tumor

Parabolic curve

Parabola