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Math Help - An other question need yr urgent help - proving a theorem!

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    Exclamation An other question need yr urgent help - proving a theorem!

    Theorem : the nth root of an integer
    is either an integer or irrational.

    Prove the more general result:
    Theorem: If x is a root of the polynomial xm + c1 xm-1 + c2 xm-2+ ... + cm = 0,
    (with the coefficients c1, c2, ... , cm all integers,
    of course), then x is either an integer or irrational.

    (Hint: suppose a/b is a root of the polynomial, and a and
    b are relatively prime. Plug into the equation above and multiply
    both sides by bm. Show that b must equal 1.)

    Incidentally, this result naturally leads to the
    definition of a quadratic integer .
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