1. **Stating the problem:** Find the limit as $x$ approaches 5 of the function $$\frac{x^2 - 4x - 5}{x - 5}$$
2. **Recall the formula and rules:** When direct substitution leads to an indeterminate form like $\frac{0}{0}$, we try to simplify the expression by factoring or other algebraic manipulation.
3. **Check direct substitution:** Substitute $x=5$:
$$\frac{5^2 - 4\times5 - 5}{5 - 5} = \frac{25 - 20 - 5}{0} = \frac{0}{0}$$ which is indeterminate.
4. **Factor the numerator:**
$$x^2 - 4x - 5 = (x - 5)(x + 1)$$
5. **Rewrite the limit:**
$$\lim_{x \to 5} \frac{(x - 5)(x + 1)}{x - 5}$$
6. **Cancel common factors:**
$$\lim_{x \to 5} \frac{\cancel{(x - 5)}(x + 1)}{\cancel{x - 5}} = \lim_{x \to 5} (x + 1)$$
7. **Evaluate the simplified limit:**
$$5 + 1 = 6$$
**Final answer:** The limit is 6.
This corresponds to option ج (c).
Limit At 5 C61317
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