What Work Is with the working class or work in general. This helps place this collection within the tradition of working class poetry. For instance, besides work, love also is a major theme for Levine in this collection. "What Work Is" is a poem primarily written for his brother, and the difficulty of expressing that love. Often enough the theme of love is expressed in a subdued way and is shadowing the bolder themes most largely associated with work. The poems feature different types of work, some of which reflect the actual work experience of the author. For instance, the poems "Fear and
Irrational number During the 14th to 16th centuries, Madhava of Sangamagrama and the Kerala school of astronomy and mathematics discovered the infinite series for several irrational numbers such as "π" and certain irrational values of trigonometric functions. Jyeṣṭhadeva provided proofs for these infinite series in the "Yuktibhāṣā". In the Middle ages, the development of algebra by Muslim mathematicians allowed irrational numbers to be treated as "algebraic objects". Middle Eastern mathematicians also merged the concepts of "number" and "magnitude" into a more general idea of real numbers, criticized Euclid's idea of ratios, developed the theory of composite ratios, and extended the concept of