1. May 21, 2014

### mafagafo

1. The problem statement, all variables and given/known data
Find B and C such that
$$\emptyset \in C$$
$$B \in C$$
$$B \subset C$$
3. The attempt at a solution
$$B=\emptyset$$
$$C=\{B\}$$
It just does not look right. Any feedback?

2. May 21, 2014

### Fredrik

Staff Emeritus
Looks good. B is clearly an element of C, and since $B=\varnothing$, this means that $\varnothing$ is an element of C. The subsets of C are $\varnothing$ and $C$. Since $B=\varnothing$, this means that B is a subset of C.

Last edited: May 21, 2014