Guided Activity

Guided Activity
The goal of this activity is to match a polynomial function to an unknown function and learn a bit about polynomial functions along the way. In other words, your goal is to match the unknown function g(x) by changing the values of the coefficients a, b, and c in your polynomial function, f(x)=y. Let the red curve on the graph be the known polynomial function, f(x). Let the dark blue curve on the graph be the unknown polynomial function, g(x). The thin curves represent individual contributions to f(x). Namely, ax2, bx, and c. Record all your observations, results, and analysis as they may be worth marks. Good hunting!

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Question

What is the y-intercept for the unknown function? What is the value of y when x=0?   -2.5

Example Data Table

More Guided Activity
You have completed the first part of the activity. Now you need to match the entire function f(x) to the unknown function. Which way is unknown function's minimum (or maximum) shifted from x=0? With c=0, can you make the red curve not cross the blue curve? Now look at how broad the unknown function is for a specific range of x. Can you match the curve?

Check Your Results