Assuming that the parabola passes through a fixed point (2, 1), it is necessary to bring this point (2, 1) into the parabolic equation to balance the equation, and so on. If it can't be balanced, it means it doesn't have to pass through a fixed point. Enter the equation with a fixed point:

Equation b = 2a+ 1=4a-b+3 is equal, which shows that the hypothesis is true. The parabola passes through a fixed point (2, 1)

2. According to the parabola y=ax2-bx+3, A is not equal to 0; Its vertex coordinates are (b/2a, 3-b 2/4a).

That is, the axis of symmetry x = b/2a；; B=2a+ 1 is brought into the sorted

X= 1+ 1/2a If the symmetry axis can be X= 1, then 1/2a=0, but the actual 1/2a cannot be equal to 0, so the statement is wrong.

3, the vertex coordinates are y = 3-b 2/4a, and b=2a+ 1 into the arrangement.

y=4-(a+ 1/4a)

When a < 0, (a+ 1/4a) has the maximum value, and the maximum value is 1 (supplement: if a>0 has the minimum value 1), so y=4-(a+ 1/4a) is below a < 0, and the maximum value of the fixed-point ordinate is 3). So this formulation is also correct.

Therefore, there are always two statements that are correct.

Your topic is wrong, it should be (-2, 1).