Respuesta :
The symbol [tex] \subset [/tex] stands for subset. So, [tex] A \subset B [/tex] means that A is a subset of B.
This means that every element in A is also an element of B, while the opposite is not necessarily true: there can be elements of B that are not elements of A.
For example, if you consider the sets
[tex] A = \{ \text{US Capitals} \},\ \ B = \{ \text{US Cities} \} [/tex]
You can see that A is a subset of B: every Capitol is a city, but most cities aren't capitols.
