Question

Use quadratic regression to find a

function that fits the following
points.
(-2,-1), (1,-1), (3,9)

Answer 1

1x² + 1x -3

Explanation:

A quadratic regression is the process of finding the equation of the parabola that best fits a set of data. As a result, we get an equation of the form:
`y=ax^2+bx+c \text{ where } a\\e0 .`

To compute manually the values of a, b and c is a rather complicated process using a technique known as least squares method.

However, we can use a scientific calculator to compute the three values and arrive at the quadratic equation

Using the points provided, the values are:

a = 1, b = 1, c = -3

The function is 1x² + 1x -3

Note that this is a best-fit function it does not necessarily pass through all 3 points but approximates. The attached graph shows that the function does indeed pass through 2 of the 3 points