Question

Which is the graph of f(x) = x2 – 2x + 3?

Answer 1

The correct answer is:

The graph will be the same width as the parent graph f(x) = x², but the vertex has been shifted to (1, 2).

Explanation:

Since the value of a, the coefficient of x², is 1, this means the graph has not been stretched or shrunk. However, since the function is different than f(x)=x², we know that the vertex is not at (0, 0). We can write the function in vertex form to find the new vertex.

To write the function in vertex form, we find the value of b/2. The value of b in this function is -2; -2/2 = -1. We then square this: (-1)² = 1. This is what we add and subtract to the function (we must do both to preserve equality), giving us:

f(x) = x²-2x+1+3-1

The first three terms of this function can be written as the square (x+(b/2))²; this is (x-1)², and gives us f(x) = (x-1)²+3-1. Combining like terms, we have:

f(x) = (x-1)²+2

This is vertex form, f(x) = a(x-h)²+k, where (h, k) is the vertex. This means the vertex is at (1, 2) instead of (0, 0).

Answer 2

To find the graph of f(x) = x^2 - 2x + 3, you can either plug in values into where the x variable stands and solve for their corresponding y-values or you can also use your graphing calculator or even Desmos works!