Write an analytic expression of quadratic function, so that its image satisfies two conditions The vertex is on the line y equals - X Without going through the origin, the analytic expression of this quadratic function can be?
If the vertex is y = - x, we can set the vertex as (h, - H), let y = a (X-H) ^ 2-h
If x = 0, y = ah ^ 2-h ≠ 0, if h ≠ 0, then a ≠ 1 / h
For example, y = 2 (x-1) ^ 2-1