How do I write the quadratic function f(x) = x² – 8x + 3 in vertex form?

To convert the quadratic function f(x) = x² – 8x + 3 into vertex form, we can use the method of completing the square.

1. Start with the function:

f(x) = x² – 8x + 3

2. Focus on the quadratic and linear terms, which are x² – 8x. To complete the square, we need to find a number that makes this a perfect square trinomial.

3. Take the coefficient of x (which is -8), divide it by 2, and then square it:

(-8 / 2)² = (-4)² = 16

4. Add and subtract this number (16) within the function:

f(x) = (x² – 8x + 16) – 16 + 3

5. Now, rewrite the expression:

f(x) = (x – 4)² – 13

Now we have the function in vertex form:

f(x) = (x – 4)² – 13

This shows that the vertex of the parabola represented by this function is at the point (4, -13).

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