f(x)=2x^2-8x+8
This is a quadratic equation, and its graph is a vertical parabola
f(x)=ax^2+bx+c
a=2>0 (positive), then the parabola opens upward
b=-8
c=8
The Vertex is the minimum point of the parabola: V=(h,k)
The abscissa of the Vertex is:
h=-b/(2a)=-(-8)/[2(2)]=8/4→h=2
The axis of symmetry is the vertical line:
x=h→x=2
Answer: The axis of symmetry for f(x) = 2x^2 − 8x + 8 is x=2