1. **State the problem:** Determine which of the given sets are subsets of the set $$A = \{1, \{2, 3, 4\}, \{5, \{6\}\}, 7, 8\}$$.
2. **Recall the definition of subset:** A set $$B$$ is a subset of $$A$$, written $$B \subseteq A$$, if every element of $$B$$ is also an element of $$A$$.
3. **Analyze each candidate subset:**
- $$\emptyset \subseteq A$$: The empty set is a subset of every set by definition.
- $$\{2, 3, 4\} \subseteq A$$: Check if elements 2, 3, and 4 are in $$A$$. They are elements inside the set $$\{2, 3, 4\}$$ which is an element of $$A$$, but 2, 3, and 4 themselves are not elements of $$A$$. So $$\{2, 3, 4\} \not\subseteq A$$.
- $$\{1, 7, 8\} \subseteq A$$: Elements 1, 7, and 8 are all elements of $$A$$, so this is a subset.
- $$\{\{2, 3, 4\}\} \subseteq A$$: The set $$\{2, 3, 4\}$$ is an element of $$A$$, so this singleton set is a subset.
- $$\{5, \{6\}\} \subseteq A$$: Check if 5 and $$\{6\}$$ are elements of $$A$$. The element $$\{5, \{6\}\}$$ is in $$A$$, but 5 alone is not an element of $$A$$, nor is $$\{6\}$$. So this is not a subset.
- $$\{\{5, \{6\}\}, 7, 8\} \subseteq A$$: The elements $$\{5, \{6\}\}$$, 7, and 8 are all elements of $$A$$, so this is a subset.
4. **Final answers:**
- $$\emptyset \subseteq A$$: True
- $$\{2, 3, 4\} \subseteq A$$: False
- $$\{1, 7, 8\} \subseteq A$$: True
- $$\{\{2, 3, 4\}\} \subseteq A$$: True
- $$\{5, \{6\}\} \subseteq A$$: False
- $$\{\{5, \{6\}\}, 7, 8\} \subseteq A$$: True
Subset Check A4C27C
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.