2023 AMC 10A Problems/Problem 21
Let be the unique polynomial of minimal degree with the following properties:
- has a leading coefficient ,
- is a root of ,
- is a root of ,
- is a root of , and
- is a root of .
The roots of are integers, with one exception. The root that is not an integer can be written as , where and are relatively prime integers. What is ?
[bold] Solution 1 [\bold]
From the problem statement, we know , , and . Therefore, we know that , , and are roots. Because of this, we can factor as , where is the unknown root. Plugging in gives , so . Therefore, our answer is , or
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