If we know that the image of a function y = ax + B passes through a point (2,1), then the description of parabola y = ax ^ 2-bx + 3 is correct If the image of a function y = ax + B passes through a point (2,1), then the parabola y = ax ^ 2-bx + 3 is described as follows: (1) passing through a fixed point (- 2,5); (2) the axis of symmetry can be x = 1; (3) passing through a fixed point (0,3), (4) when a > 0, the maximum value of the ordinate of the vertex is 3; (5) when a < 0, the minimum value of the ordinate of the vertex is 3, (6) It is possible that B = - 2A_________________ .）

If we know that the image of a function y = ax + B passes through a point (2,1), then the description of parabola y = ax ^ 2-bx + 3 is correct If the image of a function y = ax + B passes through a point (2,1), then the parabola y = ax ^ 2-bx + 3 is described as follows: (1) passing through a fixed point (- 2,5); (2) the axis of symmetry can be x = 1; (3) passing through a fixed point (0,3), (4) when a > 0, the maximum value of the ordinate of the vertex is 3; (5) when a < 0, the minimum value of the ordinate of the vertex is 3, (6) It is possible that B = - 2A_________________ .）

If the image of a function y = ax + B passes through a point (2,1), then 2A + B = 1
(1) When x = - 2, y = 4A + 2B + 3 = 2 (2a + b) + 3 = 2 + 3 = 5, over the fixed point (- 2,5), so (1) is correct
(2) The axis of symmetry is x = - (- b) / (2a) = B / 2A = (1-2a) / (2a) = 1 / (2a) - 1
When x = 1, there is 1 / (2a) - 1 = 1, and a = 1 / 4 can be obtained, so (2) is also correct
(3) When x = 0, y = 3, over fixed point (0,3), so (3) is correct
(4) When a > 0, y = (4a * 3-B ^ 2) / (4a) = (12a - (1-2a) ^ 2) / (4a) = (12a-1 + 4a-4a ^ 2) / (4a) = - A-1 / (4a) + 4 = - [a + 1 / (4a)] + 4

Given that the image of a function y = ax + B passes through a point (- 2,1), then the description of parabola y = ax-bx + 3: when a < 0, the minimum value of the ordinate of its vertex
Is 3, is not correct, the reason

This is not true because the quadratic function y = ax ^ 2-bx + 3 is a