1. **State the problem:** We have three sets:
- Universal set $\xi = \{x : x \text{ is an integer and } 1 \leq x \leq 6\}$
- Set $A = \{x : x \text{ is an integer and } 7 < 3x < 15\}$
- Set $B = \{x : x \text{ is a root of } x^2 - 8x + 15 = 0\}$
We need to find the elements of $A$ and $B$ and then place all elements of $\xi$, $A$, and $B$ in a Venn diagram.
2. **Find elements of $A$:**
Given $7 < 3x < 15$, divide all parts by 3:
$$7 < 3x < 15 \implies \frac{7}{3} < x < 5$$
Since $x$ is an integer, $x$ can be $2, 3, 4$ because $\frac{7}{3} \approx 2.33$ and $x$ must be greater than that and less than 5.
So, $A = \{3, 4\}$ (since 2 is not greater than 2.33, only 3 and 4 satisfy).
3. **Find elements of $B$:**
Solve the quadratic equation:
$$x^2 - 8x + 15 = 0$$
Factor:
$$x^2 - 8x + 15 = (x - 3)(x - 5) = 0$$
So roots are $x = 3$ and $x = 5$.
Thus, $B = \{3, 5\}$.
4. **Universal set $\xi$:**
$\xi = \{1, 2, 3, 4, 5, 6\}$.
5. **Place elements in Venn diagram:**
- Elements in $A$ only: $4$ (since 3 is also in $B$)
- Elements in $B$ only: $5$
- Elements in both $A$ and $B$ (intersection): $3$
- Elements in $\xi$ but not in $A$ or $B$: $1, 2, 6$
**Final sets:**
$$A = \{3, 4\}$$
$$B = \{3, 5\}$$
$$A \cap B = \{3\}$$
$$A - B = \{4\}$$
$$B - A = \{5\}$$
$$\xi - (A \cup B) = \{1, 2, 6\}$$
Venn Diagram Sets 95Ebf8
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.