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 was the first number proved irrational, and that article contains a number of proofs. The golden ratio is another famous quadratic irrational and there is a simple proof of its irrationality in its article. The square roots of all natural numbers which are not perfect squares are irrational and a proof may be found in quadratic irrationals. The proof above for the square root of two can be generalized using the fundamental theorem of arithmetic. This asserts that every integer has a unique factorization into primes. Using it we can show that if a rational number is not an integer