1. **Problem:** Find the limit $$\lim_{x \to -\infty} \frac{\sqrt{x^2+5}}{x-\#}$$ where \# is a constant.
2. **Formula and rules:** For limits involving infinity and square roots of quadratic expressions, use the fact that $$\sqrt{x^2 + a} = |x|\sqrt{1 + \frac{a}{x^2}}$$ and as $$x \to -\infty$$, $$|x| = -x$$ because $$x$$ is negative.
3. **Step-by-step solution:**
- Rewrite the numerator:
$$\sqrt{x^2 + 5} = |x| \sqrt{1 + \frac{5}{x^2}} = -x \sqrt{1 + \frac{5}{x^2}}$$ since $$x \to -\infty$$.
- Substitute into the limit:
$$\lim_{x \to -\infty} \frac{-x \sqrt{1 + \frac{5}{x^2}}}{x - \#}$$
- Factor $$x$$ from the denominator:
$$x - \# = x \left(1 - \frac{\#}{x}\right)$$
- So the limit becomes:
$$\lim_{x \to -\infty} \frac{-x \sqrt{1 + \frac{5}{x^2}}}{x \left(1 - \frac{\#}{x}\right)}$$
- Cancel $$x$$:
$$\lim_{x \to -\infty} \frac{\cancel{-x} \sqrt{1 + \frac{5}{x^2}}}{\cancel{x} \left(1 - \frac{\#}{x}\right)} = \lim_{x \to -\infty} \frac{-\sqrt{1 + \frac{5}{x^2}}}{1 - \frac{\#}{x}}$$
- As $$x \to -\infty$$, $$\frac{5}{x^2} \to 0$$ and $$\frac{\#}{x} \to 0$$, so:
$$= \frac{-\sqrt{1 + 0}}{1 - 0} = \frac{-1}{1} = -1$$
**Final answer:** $$\boxed{-1}$$
Limit Infinity 8Af8B8
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