An irrational number is a real number that cannot be written as a fraction. Irrational numbers have decimal expansions that neither terminate nor become periodic.
An irrational number is a number that cannot be expressed as a fraction p/q for any integers p and q. Irrational numbers have decimal expansions that neither terminate nor become periodic. Every transcendental number is irrational. There is no standard notation for the set of irrational numbers, but the notations Q^_, R - Q, or R\Q, where the bar, minus sign, or backslash indicates the set complement of the rational numbers Q over the reals R, could all be used.
algebraic integer | algebraic number | almost integer | continuum | decimal expansion | Dirichlet function | e | Ferguson-Forcade algorithm | Gelfond's theorem | Hurwitz's irrational number theorem | near noble number | noble number | pi | Pythagoras's constant | Pythagoras's theorem | q-harmonic series | quadratic surd | rational number | regular number | repeating decimal | Segre's theorem | transcendental number
middle school level (California grade 7 standard)