I would assume this means to extract the functionality that relates explicitly to the multiplication of polynomials and place that into a function and pass the values as needed to this function. What you have at the moment is a lump of code that will only calculate for one set of particular values and makes it difficult to reuse the benefits of code already written without rewriting substantial amounts of it.
To get you started the declaration of this would look something like
With reagrds to the header I don't know what that is .. Java doesn't use header filesperhaps you can get some clarification from whoever assigned you this project!
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