发布日期 ： 2019-11-14 02:10:47 UTC
分类 ： Algebraic
The parabolic equation refers to the parabolic trajectory equation, which is a method of expressing the parabola with equations.The parabola can be drawn according to the parabolic equation on the geometric plane.The parabola can also be viewed as a quadratic function image under suitable coordinate transformation.
When the apex of the parabolic equation: (h, k), focus: (x1, y1), then the vertex equation of the parabola:
(X-h)<sup>2</sup> = 4a(Y-k)； ( a = √<span style="TEXT-DECORATION: overline">(h-x1) * (h-x1) + (k - y1) * (k-y1)</span> )
Standard form of parabolic equation:
Y = (1/4a)X<sup>2</sup> - (h/2a)X + (k + h<sup>2</sup>/4a)；( a = √<span style="TEXT-DECORATION: overline">(h-x1) * (h-x1) + (k - y1) * (k-y1)</span> )
<div align=left> <img src="/static/upload/73/734f3c12-b903-11ea-a97b-00163e0618d6_m.jpg" style="width:50%"/> </div>
Vertex: X: 2; Y: 8
Focus: X: 4; Y: 4
Click "Calculate" to output the result
Standard equation: (X +2)^2 = 17.8885(Y +8)
Vertex equation: Y = 0.0559X^2 -0.2236X +8.2236