State whether each of the following set is finite or infinite :
The set of letters in the English alphabet
What universal set $(s)$ would you propose for each of the following :
The set of isosceles triangles
Write the following as intervals :
$\{ x:x \in R, - 12\, < \,x\, < \, - 10\} $
In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.
If $A \not\subset B$ and $B \not\subset C,$ then $A \not\subset C$
Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 8\, .......\, A $