Rational Root Theorem

In algebra, the rational root theorem (or rational root test) states a constraint on rational solutions (or roots) of the polynomial equation

with integer coefficients.

If a0 and an are nonzero, then each rational solution x, when written as a fraction x = p/q in lowest terms (i.e., the greatest common divisor of p and q is 1), satisfies

  • p is an integer factor of the constant term a0, and
  • q is an integer factor of the leading coefficient an.

Thus, a list of possible rational roots of the equation can be derived using the formula .

The rational root theorem is a special case (for a single linear factor) of Gauss's lemma on the factorization of polynomials. The integral root theorem is a special case of the rational root theorem if the leading coefficient an = 1.

Read more about Rational Root Theorem:  Example

Famous quotes containing the words rational, root and/or theorem:

    We fetch fire and water, run about all day among the shops and markets, and get our clothes and shoes made and mended, and are the victims of these details, and once in a fortnight we arrive perhaps at a rational moment.
    Ralph Waldo Emerson (1803–1882)

    There is a certain class of unbelievers who sometimes ask me such questions as, if I think that I can live on vegetable food alone; and to strike at the root of the matter at once,—for the root is faith,—I am accustomed to answer such, that I can live on board nails. If they cannot understand that, they cannot understand much that I have to say.
    Henry David Thoreau (1817–1862)

    To insure the adoration of a theorem for any length of time, faith is not enough, a police force is needed as well.
    Albert Camus (1913–1960)