①AC < 0； ② the root of the equation ax2+bx+c = 0 is x 1 =- 1, and x2 = 3.
③ a+b+c > 0 ④ when x > 1, y increases with the increase of x.
The correct statement is _ _ _ ① ② ④ _ _ _ _. (Fill in the serial number of the correct answer on the line)
2.(08 Tianjin) Translate the parabola upward by 5 units, and the analytical formula of the parabola is ().
A.B. C. D。
3.(08 Tianjin) The parabola is known. If the point (0,5) and the point are symmetrical about the parabola, the coordinate of the point is (4,5).
(a) row x = 1 (b) row x = 3 (c) row x =- 1 (d) row x =-3.
4.(08 Yiwu, Zhejiang) The image of the known quadratic function is one of the following images, with the value of.
A.- 1 B . 1 C. -3 D. -4
5. (Longyan City) 15. Known function image as shown in the figure, then the following conclusion is correct ().
A.a>0，c>0 B.a