Real numbers
Most applications of mathematics use real numbers. For purposes of such applications,it suffices to think of a real number as a decimal. A rational number is one that may be written as a finite or infinite repeating decimal, such as
-5/2=-2.5, 1, 13/3 = 4.333... (rational numbers).
An irrational number has an infinite decimal representation whose digits form no repeating pattern, such as
-sqrt(2)=-1.414214..., pi = 3.14159... (irrational numbers).
We use four types of inequalities to compare real numbers.
x <> y , x is greater than y
x >= y , x is greater than or equal to y
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