How do you find the coordinates for the vertex of $f(x)=2x^2-8x+1$ ?

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Answer 1 · 2016-11-13T20:44:58

The vertex is at $(2,-7)$ .

$f(x)=2x^2-8x+1$

We have to put the equation into vertex form by completing the square.
$f(x)=2[x^2-4x+1/2]$

$f(x)=2[(x-2)^2-7/2]$

$f(x)=2(x-2)^2-7$

The vertex is at $(2,-7)$ .

Check using the graph:
graph{2x^2-8x+1 [-10, 10, -7.76, 2.24]}

How do you find the coordinates for the vertex of f(x)=2x^2-8x+1f(x)=2x^2-8x+1?