If A = {1, {2, 3}}, find P(A) and n {P(A)}.

Let {2,3} = x

Now, $A=\{1, x\}$

Subsets of $A$ are $\phi,\{1\},\{x\},\{1, x\}$

$\Rightarrow$ Subsets of $A$ are $\phi,\{1\},\{2,3\},\{1,\{2,3\}\}$

Now, $n\{P(A)\}=2^{m}$, where $m=n(A)=2$

$\Rightarrow \mathrm{n}\{\mathrm{P}(\mathrm{A})\}=2^{2}=4$