MyWikiBiz, Author Your Legacy — Monday December 02, 2024
Jump to navigationJump to search
33 bytes added
, 19:30, 3 July 2008
Line 28: |
Line 28: |
| The briefest expression for logical truth is the empty word, usually denoted by <math>\varepsilon\!</math> or <math>\lambda\!</math> in formal languages, where it forms the identity element for concatenation. To make it visible in this text, I denote it by the equivalent expression "<math>((~))\!</math>", or, especially if operating in an algebraic context, by a simple "<math>1\!</math>". Also when working in an algebraic mode, I use the plus sign "<math>+\!</math>" for exclusive disjunction. Thus, we may express the following paraphrases of algebraic forms: | | The briefest expression for logical truth is the empty word, usually denoted by <math>\varepsilon\!</math> or <math>\lambda\!</math> in formal languages, where it forms the identity element for concatenation. To make it visible in this text, I denote it by the equivalent expression "<math>((~))\!</math>", or, especially if operating in an algebraic context, by a simple "<math>1\!</math>". Also when working in an algebraic mode, I use the plus sign "<math>+\!</math>" for exclusive disjunction. Thus, we may express the following paraphrases of algebraic forms: |
| | | |
− | :{| cellpadding="4"
| + | <center> |
− | | ''A'' + ''B''
| + | <p><math>\begin{matrix} |
− | | =
| + | x + y & = & (x, y) |
− | | (''A'', ''B'')
| + | \end{matrix}</math></p> |
− | |-
| |
− | | ''A'' + ''B'' + ''C''
| |
− | | =
| |
− | | ((''A'', ''B''), ''C'')
| |
− | | =
| |
− | | (''A'', (''B'', ''C''))
| |
− | |}
| |
| | | |
− | One should be careful to observe that these last two expressions are not equivalent to the form (''A'', ''B'', ''C'').
| + | <p><math>\begin{matrix} |
| + | x + y + z & = & ((x, y), z) & = & (x, (y, z)) |
| + | \end{matrix}</math></p> |
| + | </center> |
| + | |
| + | It is important to note that the last expressions are not equivalent to the triple bracket expression <math>(x, y, z).\!</math> |
| | | |
| <font face="courier new"> | | <font face="courier new"> |