Miscellaneous Signs and Symbols
| Sign | Example | Meaning and verbal equivalent | Remarks |
|---|---|---|---|
| ≝ |
a ≝ b | a is by definition equal to b | := is also used |
| = | a = b | a equals b | ≡ may be used to emphasize that a particular equality is an identity. |
| ≠ | a ≠ b | a is not equal to b | may be used to emphasize that a is not identically equal to b. |
| ≙ | a ≙ b | a corresponds to b | On a 1:106 map: 1 cm ≙ 10 km. |
| ≈ | a ≈ b | a is approximately equal to b | The symbol ≃ is reserved for "is asymptotically equal to". |
| ∼ ∝ |
a ∼ b a ∝ b |
a is proportional to b | |
| < | a < b | a is less than b | |
| > | a > b | a is greater than b | |
| ≤ | a ≤ b | a is less than or equal to b | The symbol ≦ is also used. |
| ≥ | a ≥ b | a is greater than or equal to b | The symbol ≧ is also used. |
| ≪ | a ≪ b | a is much less than b | |
| ≫ | a ≫ b | a is much greater than b | |
| ∞ | infinity | ||
{} |
(a+b)c c {a+b}c a+bc |
ac+bc, parentheses ac+bc, square brackets ac+bc, braces ac+bc, angle brackets |
In ordinary algebra, the sequence of, {}, in order of nesting is not standardized. Special uses are made of, {}, in particular fields. |
| ∥ | AB ∥ CD | the line AB is parallel to the line CD | |
| ABCD | the line AB is perpendicular to the line CD |
Read more about this topic: ISO 31-11
Famous quotes containing the words signs and/or symbols:
“Time has an undertaking establishment on every block and drives his coffin nails faster than the steam riveters rivet or the stenographers type or the tickers tick out fours and eights and dollar signs and ciphers.”
—John Dos Passos (1896–1970)
“And into the gulf between cantankerous reality and the male ideal of shaping your world, sail the innocent children. They are right there in front of us—wild, irresponsible symbols of everything else we can’t control.”
—Hugh O’Neill (20th century)