1. **State the problem:** We are given the differential equation $$\frac{dy}{dx} = \frac{x^2 + 1}{1 - x}$$ and asked to analyze or solve it.
2. **Understand the equation:** This is a first-order ordinary differential equation expressing the derivative of $y$ with respect to $x$.
3. **Rewrite the equation:** We can write it as $$dy = \frac{x^2 + 1}{1 - x} dx$$ to prepare for integration.
4. **Integrate both sides:** To find $y$, integrate the right side with respect to $x$:
$$y = \int \frac{x^2 + 1}{1 - x} dx + C$$
5. **Simplify the integrand:** Perform polynomial division or rewrite the fraction:
Divide $x^2 + 1$ by $1 - x$:
$$\frac{x^2 + 1}{1 - x} = -x - 1 - \frac{x}{1 - x}$$
Explanation: Because
$$x^2 + 1 = (1 - x)(-x - 1) + x$$
6. **Rewrite the integral:**
$$y = \int (-x - 1) dx - \int \frac{x}{1 - x} dx + C$$
7. **Integrate the first part:**
$$\int (-x - 1) dx = -\frac{x^2}{2} - x$$
8. **Integrate the second part:**
Rewrite $$\frac{x}{1 - x} = \frac{1 - (1 - x)}{1 - x} = \frac{1}{1 - x} - 1$$
So,
$$- \int \frac{x}{1 - x} dx = - \int \left( \frac{1}{1 - x} - 1 \right) dx = - \int \frac{1}{1 - x} dx + \int 1 dx$$
9. **Integrate each term:**
$$- \int \frac{1}{1 - x} dx = -(-\ln|1 - x|) = \ln|1 - x|$$
and
$$\int 1 dx = x$$
10. **Combine all parts:**
$$y = -\frac{x^2}{2} - x + \ln|1 - x| + x + C = -\frac{x^2}{2} + \ln|1 - x| + C$$
11. **Final answer:**
$$\boxed{y = -\frac{x^2}{2} + \ln|1 - x| + C}$$
This is the general solution to the differential equation.
Solve Dy Dx D7Bbba
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