Hi
Using the vertex form of a parabola,where(h,k) is the vertex
f(x)= 2x^2-4x+1 |putting into the vertex form by completing the square
f(x)= 2[x^2-2] +1
f(x)= 2[(x - 1)^2 - 1] + 1
f(x)= 2(x - 1)^2 -2 + 1
f(x)= 2(x - 1)^2 -1 |vertex is Pt(1, -1)
f(x) is increasing from -1 to infinity