∫∠AOC = 30，AC= 1.5

∴OC= 1.5× root number 3 = 1.5 root number 3,

∴ The coordinate of point A is (1.5 root number 3,1.5);

(2) Because we know its vertex coordinates, let the vertex y=a(x+k)? +h

First of all, the abscissa is 2, so 2+k=0 is the smallest, and k=-2, and because the ordinate is 2, when a(x+k)? When =0, H=2.

So y=- 1/2(x-2)? +2

(3)①∵ When x= 1.5 radical number 3, y≠ 1.5,

∴ Xiao Qiang can't directly throw the ball into the basket from point O;

② When y= 1.5, 1.5=- 1/2(x-2)? +2

The solution is x 1= 1 (minus), x2=3,

∫3 > 1.5 radical number 3,

∴ Xiao Qiang only needs to retreat (3- 1.5 root number 3) meters, so that the shot just now can directly hit the point A of the basket.

You don't have a picture of this problem ... some people think that point A is the vertex ... so it can't be solved at all.