quadratic surd

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quadratic surd

[kwä′drad·ik ‚sərd]
(mathematics)
A square root of a rational number that is itself an irrational number.
References in periodicals archive ?
Obviously, we have that [alpha] is a quadratic irrational, and [lambda] [member of] Q([alpha]) by Lemma 3.
In a previous paper [3], for any positive integer we introduced the notion of real quadratic fields with period l of minimal type (see Definition below) by using the simple continued Fraction expansions with period l of certain quadratic irrationals, and proved that there exist exactly 51 real quadratic fields of class number 1 that are not of minimal type, with one more possible exception ([3, Proposition 4.