Pearson Algebra 2 Common Core, 2011
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Pearson Algebra 2 Common Core, 2011 View details
9. Transforming Polynomial Functions
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Exercise 21 Page 343

We want to find a quartic function with the given values as its only real zeros.
To do so, we can write the function as the product of and another expression of degree with no real roots — for example,
Let's simplify the above by using the Distributive Property.
Distribute
Distribute and Simplify
We found that is a quartic function with and as its only real zeros. Note that, since there are infinite quartic functions with only the two given real zeros, this is just an example solution.

Alternative Solution

Solving the exercise by using transformations of a graph.

If you like graphs, there is another way of solving this exercise. Consider the parent function

Since the difference between the given zeros is four, we have to find a quartic function where the roots are units apart, and having them centered at is the easiest. Then we can use translations to move the graph over to the correct place. Let's find a quartic with zeros at because that will add up to
To do so, we need to translate the parent function units down. Therefore, we need to consider the function

Finally, and are unit to the right of and respectively.

This means that we need to translate the last function unit to the right. By doing this, we can obtain the function

We can see that is a quartic function with and as its only real zeros. Note that, although this function is different than the one we found using the algebraic method, it is also a correct answer.