Search results
Results from the WOW.Com Content Network
The first use of an equals sign, equivalent to + = in modern notation. From The Whetstone of Witte (1557) by Robert Recorde. Recorde's introduction of =."And to avoid the tedious repetition of these words: "is equal to" I will set as I do often in work use, a pair of parallels, or twin lines of one [the same] length, thus: ==, because no 2 things can be more equal." [5]
3. Between two groups, may mean that the second one is a proper subgroup of the first one. ≤ 1. Means "less than or equal to". That is, whatever A and B are, A ≤ B is equivalent to A < B or A = B. 2. Between two groups, may mean that the first one is a subgroup of the second one. ≥ 1. Means "greater than or equal to".
In mathematics, equivalent definitions are used in two somewhat different ways. First, within a particular mathematical theory (for example, Euclidean geometry ), a notion (for example, ellipse or minimal surface ) may have more than one definition.
Any equivalence relation is the negation of an apartness relation, though the converse statement only holds in classical mathematics (as opposed to constructive mathematics), since it is equivalent to the law of excluded middle. Each relation that is both reflexive and left (or right) Euclidean is also an equivalence relation.
In mathematics, the triple bar is sometimes used as a symbol of identity or an equivalence relation (although not the only one; other common choices include ~ and ≈). [ 7 ] [ 8 ] Particularly, in geometry , it may be used either to show that two figures are congruent or that they are identical. [ 9 ]
A rival programming-language usage was pioneered by the original version of ALGOL, which was designed in 1958 and implemented in 1960. ALGOL included a relational operator that tested for equality, allowing constructions like if x = 2 with essentially the same meaning of = as the conditional usage in mathematics. The equal sign was reserved for ...
The corresponding logical symbols are "", "", [6] and , [10] and sometimes "iff".These are usually treated as equivalent. However, some texts of mathematical logic (particularly those on first-order logic, rather than propositional logic) make a distinction between these, in which the first, ↔, is used as a symbol in logic formulas, while ⇔ is used in reasoning about those logic formulas ...
The first use of an equals sign, equivalent to 14x + 15 = 71 in modern notation. From The Whetstone of Witte by Robert Recorde of Wales (1557). [1]In mathematics, an equation is a mathematical formula that expresses the equality of two expressions, by connecting them with the equals sign =.