http://img23.imageshack.us/img23/6430/whatwhathw.jpg

OK, I have no idea what this is asking... I don't know what to do. Can someone help please?? thanks.

Printable View

- Mar 3rd 2009, 11:18 PMqtpipiNeed help deriving formula for a sum/polynomial stuff
http://img23.imageshack.us/img23/6430/whatwhathw.jpg

OK, I have no idea what this is asking... I don't know what to do. Can someone help please?? thanks. - Mar 6th 2009, 01:44 PMGrandadRoots of a polynomial
Hello qtpipiFirst of all, let me write out what the question is asking. The first expression means:

And to say it has zeros means

And then, we are to derive a formula for

So, using the Remainder Theorem, are factors of .

Since there are of these factors, and is a polynomial of degree , this means that we can write as:

(This is what the expression means.)

Now the coefficient of is . So . And the coefficient of in the expansion of is which is . So:

So how do we find ?

Replace by :

which has zeros at

and

and, using the same method as before, the sum of the roots of this polynomial is

Grandad