<p>Whether 0.999 equals 1 is the subject of bitter dispute in countless online forums</p>
Real numbers include all the numbers that can be found on the number line, including both rational and irrational numbers. They are used in various mathematical contexts and are fundamental to calculus and analysis.
An infinite series is the sum of the terms of an infinite sequence. It is a fundamental concept in mathematics, particularly in calculus, where it is used to define functions and analyze convergence.