It is known that the common point of the parabola y = ax ^ 2 = BX + C and X axis is a (- 1,0) B (3,0) and Y axis is C, and the vertex is d If the triangle ABC is a right triangle, try to find the value of A Q2: is there a non-zero constant a that makes ABCD on a circle? y=aX^2+bX+c

It is known that the common point of the parabola y = ax ^ 2 = BX + C and X axis is a (- 1,0) B (3,0) and Y axis is C, and the vertex is d If the triangle ABC is a right triangle, try to find the value of A Q2: is there a non-zero constant a that makes ABCD on a circle? y=aX^2+bX+c

If the triangle ABC is a right triangle, the ordinate of | C point | = root 3 can be obtained by projective theorem, which can be divided into root 3 and - root 3. A = (root 3) / 2 and - (root 3) / 22 can be obtained respectively