1. **State the problem:**
Solve the inequality $$\frac{x^2 + 1}{2x + 1} > 0$$ and determine the domain.
2. **Domain determination:**
The denominator cannot be zero, so:
$$2x + 1 \neq 0$$
$$2x \neq -1$$
$$x \neq -\frac{1}{2}$$
Thus, the domain is $$\mathbb{R} \setminus \left\{ -\frac{1}{2} \right\}$$.
3. **Analyze numerator:**
The numerator is $$x^2 + 1$$.
Since $$x^2 \geq 0$$ for all real $$x$$, and adding 1 makes it strictly positive:
$$x^2 + 1 > 0 \quad \forall x \in \mathbb{R}$$.
4. **Analyze denominator sign:**
The sign of the fraction depends on the denominator since numerator is always positive.
We want:
$$\frac{x^2 + 1}{2x + 1} > 0$$
Since numerator > 0, this inequality holds when denominator > 0:
$$2x + 1 > 0$$
$$2x > -1$$
$$x > -\frac{1}{2}$$.
5. **Final solution:**
Domain: $$\mathbb{R} \setminus \left\{ -\frac{1}{2} \right\}$$
Inequality holds for:
$$x > -\frac{1}{2}$$
Therefore, the solution set is:
$$\boxed{\left(-\frac{1}{2}, +\infty \right)}$$.
Rational Inequality D265C4
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