Difference between different and does not belong to? I know this is a dumb question but...
Is $x ≠ 1,3,5$ the same as $x$ does not belong to {$1,3,5$}, for example ?

Sorry for the formatting.
Btw, anyone has a link with mathjax's commands I guess?

Thanks in advance.
 A: Using the set notation has benefits of its own. For eg. once you define how to want an arbitrary set $S$ to look like, the name $S$ becomes an alias for that definition forever. So, you are saved from a ton of writing by referring to $S$ only and not individually to its elements.
So, while writing a proof, instead of writing and rewriting $x\ne1$ and $x\ne2$ and $x\ne3$, you can just write $x\notin S$ where $S=\{1,2,3\}$ and you are done. More over, you can't just give commas in between as in the question. One good reason for that is because the operations "logical-and" & "logical-or" are not conveyed very properly by the comma notation.
Note: Refer to the comment by @Erick Wong in the comments below. This provides another valid perspective.
A: $x \neq 1, 3, 5$ isn't super standard notation, but if someone wrote it out at random I'd assume they meant $x \neq 1$ and $x \neq 3$ and $x \neq 5,$ or $x \not\in \{1, 3, 5\}$ for short.
A: $x\notin (1,3,5)$ means that $x$ is not a member of a set.  The set is defined as elements, which could be letters, intervals or anything else.  $x\ne 1$, etc.  means that equality is defined which is no necessarily true, unless equality is defined by identity.
Simple example $1+2=3$, but for set membership $\{1+2\}$ is not the same as $\{3\}$.
