Infinity symbol symbol is encoded in Unicode at and in LaTeX as codice_1: formula_4. The Unicode set of symbols also includes several variant forms of the infinity symbol, that are less frequently available in fonts: , and in block Miscellaneous Mathematical Symbols-B. The acid-free paper symbol mentioned above is encoded separately as . Infinity symbol The infinity symbol (sometimes called the lemniscate) is a mathematical symbol representing the concept of infinity. The shape of a sideways figure eight has a long pedigree; for instance, it appears in the cross of Saint Boniface, wrapped around the bars of a Latin cross. However, John
Extended real number line Extended real number line In mathematics, the affinely extended real number system is obtained from the real number system by adding two elements: and (read as positive infinity and negative infinity respectively). These new elements are not real numbers. It is useful in describing various limiting behaviors in calculus and mathematical analysis, especially in the theory of measure and integration. The affinely extended real number system is denoted formula_1 or or . When the meaning is clear from context, the symbol is often written simply as . We often wish to describe the behavior of a function formula_2, as either