118
edits
Changes
Jump to navigation
Jump to search
Line 1:
Line 1: − They are called "real" because they actually exist as quantities in the real world, i.e. as measures, weights, temperatures. In contrast, the [[imaginary number]]s are just an abstract concept, but do not exist concretely in the real world.+
fixing misconception--please see talk
'''Real numbers''' are numbers that can be represented by some infinite or finite [[decimal]] representation, such as 0.707106781187...
'''Real numbers''' are numbers that can be represented by some infinite or finite [[decimal]] representation, such as 0.707106781187...
The term "real number" exists for historical reasons; it was once thought that such numbers "actually" existed (hence the word "real"), in contrast to the supposed non-existence of [[imaginary number]]s. However, advances in [[complex analysis]] in the 19th century revealed that imaginary numbers do, in fact, exist, and the terminology of "real" and "imaginary" is now understood to be just that--terminology.
In classical physics, measurements of things that can vary smoothly and continuously, like [[speed]] or [[temperature]], are treated as real numbers.
In classical physics, measurements of things that can vary smoothly and continuously, like [[speed]] or [[temperature]], are treated as real numbers.