written to the left of . When a coefficient is one, it is usually omitted (e.g. is written ). Likewise when the exponent (power) is one, (e.g. is written ), and, when the exponent is zero, the result is always 1 (e.g. is written , since is always ). Algebraic and other mathematical expressions The table below summarizes how algebraic expressions compare with several other types of mathematical expressions by the type of elements they may contain, according to common but not universal conventions. A rational algebraic expression (or rational expression) is an algebraic expression that can be written as a quotient of polynomials, such as . An irrational algebraic expression is one that is not rational, such as . See also Algebraic equation Algebraic function Analytical expression Arithmetic expression Closed-form expression Expression (mathematics) Precalculus Polynomial Term (logic) Notes References External links Elementary algebra