1. **Problem statement:** Calculate the binomial coefficient $\binom{8}{2}$.
2. **Formula:** The binomial coefficient $\binom{n}{k}$ is calculated by the formula:
$$\binom{n}{k} = \frac{n!}{k!(n-k)!}$$
where $n!$ denotes the factorial of $n$.
3. **Apply the formula:** For $n=8$ and $k=2$:
$$\binom{8}{2} = \frac{8!}{2!(8-2)!} = \frac{8!}{2!6!}$$
4. **Simplify factorials:**
$$8! = 8 \times 7 \times 6!$$
So,
$$\binom{8}{2} = \frac{8 \times 7 \times 6!}{2! \times 6!}$$
5. **Cancel common factors:**
$$\binom{8}{2} = \frac{8 \times 7 \times \cancel{6!}}{2! \times \cancel{6!}} = \frac{8 \times 7}{2!}$$
6. **Calculate $2!$:**
$$2! = 2 \times 1 = 2$$
7. **Final calculation:**
$$\binom{8}{2} = \frac{8 \times 7}{2} = \frac{56}{2} = 28$$
**Answer:** $\boxed{28}$
Binomial Coefficient 2441A4
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