Let $A, B$ and $C$ be three sets. If $A \in B$ and $B \subset C$, is it true that $A$ $\subset$ $C$ ?. If not, give an example.
No. Let $A=\{1\}, B=\{\{1\}, 2\}$ and $C=\{\{1\}, 2,3\} .$ Here $A \in B$ as $A=\{1\}$ and $B \subset C$. But $A \not\subset C$ as $1 \in A$ and $1 \notin C$
Note that an element of a set can never be a subset of itself.
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\{1,2,3\}\subset A$
Consider the sets
$\phi, A=\{1,3\}, B=\{1,5,9\}, C=\{1,3,5,7,9\}$
Insert the symbol $\subset$ or $ \not\subset $ between each of the following pair of sets:
$A \ldots C$
If $Q = \left\{ {x:x = {1 \over y},\,{\rm{where \,\,}}y \in N} \right\}$, then
Decide, among the following sets, which sets are subsets of one and another:
$A = \{ x:x \in R$ and $x$ satisfy ${x^2} - 8x + 12 = 0 \} ,$
$B=\{2,4,6\}, C=\{2,4,6,8 \ldots\}, D=\{6\}$
For an integer $n$ let $S_n=\{n+1, n+2, \ldots \ldots, n+18\}$. Which of the following is true for all $n \geq 10$ ?