Question 1201818
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By the instruction determine "the y value", I assume it means the FIRST SEVERAL y VALUES, for x values of 1, 2, 3,....<br>
The first differences are then the differences between successive y values; and the second differences are the differences between successive first differences.<br>
If you know all that, then I don't know why you are asking us to do your work for you.  If you don't know all that, then I don't know why you are working on a problem like this....<br>
Assuming that you can do the work yourself, note that, since the leading term of the polynomial is x^2, you should find that the second differences will all be the constant 2.<br>
If you try to work the problem and encounter difficulties, re-post the problem, telling us where you are having the difficulties.<br>