What do more than or less than sign with a line through them mean?

$\begingroup$

What do these symbols where the arrow point to mean? Does it mean not less then? If that's the case, why do we write it that way and not > if they are the same?

$\endgroup$ 3

2 Answers

$\begingroup$

$0\not<1$ means ‘$0$ is not less than $1$’, just as $a\ne b$ means ‘$a$ is not equal to $b$’. This is not the same as $0>1$; it is the same as $0\ge 1$, but in this case I suspect that $p$ is $0<1$, and the writer preferred to write the negated relation in a way that made the connection with $\sim p$ (‘not $p$’) obvious

$\endgroup$ $\begingroup$

Pretty much for any logical symbol in mathematics, a diagonal line through it means the logical negation. Examples $\notin$, $\neq$, $\nexists$, etc.

$\endgroup$

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password Submit

Post as a guest

Post Your Answer Discard

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy