Real number
The real numbers include all the rational numbers , such as the integer −5 and the fraction 4/3 , and all the irrational numbers , such as ( 1 . 41421356 . . . , the square root of 2 , an irrational algebraic number ) . 
<triplet> rational number <subj> integer <obj> has parts of the class <triplet> square root of 2 <subj> irrational number <obj> instance of <subj> algebraic number <obj> instance of