[填空题]
Let $f(x)=2 x^{2}+4 x+p$ , for $x \in \mathbb{R}$ , where $p \in \mathbb{Z}$ .
1. The equation f(x)=0 has two equal roots.
1. Write down the value of the discriminant of f .
2. Show that p=2 .
2. For the graph of f , find:
1. the equation of the axis of symmetry. x =
2. the coordinates of the vertex; (a,b) a = b =
3. Write down the solution to the equation f(x)=0 . x =
4. The function f can be written in the form $f(x)=a(x-h)^{2}+k$ . Find the values of a, h and k . a = h = k =
5. The graph of a function g is obtained from the graph of f by a reflection in the x -axis. Find the coordinates of the vertex of the graph of g . (a,b) a = b =
