Solvable For P 9C7556
1. **Problem Statement:** Solve the differential equation solvable for $p=\frac{dy}{dx}$:
$$x\left(\frac{dy}{dx}\right)^2 + (y - 1 - x^2) \frac{dy}{dx} - x(y - 1) = 0$$
2. **Formula and Approach:** This is a quadratic equation in $p=\frac{dy}{dx}$:
$$a p^2 + b p + c = 0$$
where
$$a = x, \quad b = y - 1 - x^2, \quad c = -x(y - 1)$$
We solve for $p$ using the quadratic formula:
$$p = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
3. **Calculate the discriminant:**
$$\Delta = b^2 - 4ac = (y - 1 - x^2)^2 - 4x(-x(y - 1)) = (y - 1 - x^2)^2 + 4x^2(y - 1)$$
4. **Simplify the discriminant:**
Expand $(y - 1 - x^2)^2$:
$$= (y - 1)^2 - 2x^2(y - 1) + x^4$$
Add $4x^2(y - 1)$:
$$\Delta = (y - 1)^2 - 2x^2(y - 1) + x^4 + 4x^2(y - 1) = (y - 1)^2 + 2x^2(y - 1) + x^4$$
Rewrite:
$$\Delta = (y - 1)^2 + 2x^2(y - 1) + x^4 = \left(x^2 + y - 1\right)^2$$
5. **Substitute back into formula for $p$:**
$$p = \frac{-(y - 1 - x^2) \pm (x^2 + y - 1)}{2x}$$
6. **Evaluate the two cases:**
- For the plus sign:
$$p = \frac{-(y - 1 - x^2) + (x^2 + y - 1)}{2x} = \frac{0}{2x} = 0$$
- For the minus sign:
$$p = \frac{-(y - 1 - x^2) - (x^2 + y - 1)}{2x} = \frac{-y + 1 + x^2 - x^2 - y + 1}{2x} = \frac{2(1 - y)}{2x} = \frac{1 - y}{x}$$
7. **Solve each differential equation:**
- Case 1: $\frac{dy}{dx} = 0$ implies $y = C_1$ (constant).
- Case 2: $\frac{dy}{dx} = \frac{1 - y}{x}$
Rewrite:
$$\frac{dy}{dx} + \frac{y}{x} = \frac{1}{x}$$
This is a linear first-order ODE.
8. **Integrating factor:**
$$\mu(x) = e^{\int \frac{1}{x} dx} = e^{\ln|x|} = x$$
Multiply both sides by $x$:
$$x \frac{dy}{dx} + y = 1$$
Left side is derivative of $xy$:
$$\frac{d}{dx}(xy) = 1$$
Integrate:
$$xy = x + C_2$$
9. **Solve for $y$:**
$$y = 1 + \frac{C_2}{x}$$
10. **Final family of solutions:**
$$\boxed{y = C_1 \quad \text{or} \quad y = 1 + \frac{C_2}{x}}$$
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**Slug:** solvable-for-p
**Subject:** differential equations
**Desmos:** {"latex":"y=1+\frac{C}{x}","features":{"intercepts":true,"extrema":true}}
**q_count:** 6
(Note: Only the first problem is solved as per instructions.)