Question

The number of elements in the power set $P\left(S\right)$ of the set $S=\left\{\right(\varphi ),1,(2,3\left)\right\}$ is:

• A. 2
• B. 4
• C. 8
• D. None of these

Answer 1

The correct option is C 8

If a set has $n$ elements then its powers set has $2^n$ elements.
Given set $S=\left\{\right(\varphi ),1,(2,3)$}
Number of elements in $S=3$
$\therefore$ The number of elements in powerset $\left(S\right)=2^3=8$