1. **State the problem:** Given the system of equations:
$$x^2 = 2025y + x$$
$$y^2 = 2025x + y$$
Find the value of $$\frac{x}{y^2} + \frac{y}{x^2}$$.
2. **Rewrite the equations:**
From the first equation:
$$x^2 - x = 2025y$$
From the second equation:
$$y^2 - y = 2025x$$
3. **Express in terms of $$x$$ and $$y$$:**
Divide the first equation by $$y^2$$ (assuming $$y \neq 0$$):
$$\frac{x^2}{y^2} - \frac{x}{y^2} = 2025 \frac{y}{y^2} = \frac{2025}{y}$$
Divide the second equation by $$x^2$$ (assuming $$x \neq 0$$):
$$\frac{y^2}{x^2} - \frac{y}{x^2} = 2025 \frac{x}{x^2} = \frac{2025}{x}$$
4. **Define variables:**
Let $$A = \frac{x}{y^2}$$ and $$B = \frac{y}{x^2}$$.
5. **Rewrite the above in terms of $$A$$ and $$B$$:**
From step 3:
$$\frac{x^2}{y^2} = x \cdot A$$ because $$\frac{x^2}{y^2} = x \cdot \frac{x}{y^2} = xA$$.
Similarly, $$\frac{y^2}{x^2} = y \cdot B$$.
So the two equations become:
$$xA - A = \frac{2025}{y}$$
$$yB - B = \frac{2025}{x}$$
6. **Rewrite as:**
$$A(x - 1) = \frac{2025}{y}$$
$$B(y - 1) = \frac{2025}{x}$$
7. **Sum $$A + B$$:**
We want to find $$A + B = \frac{x}{y^2} + \frac{y}{x^2}$$.
8. **Try to find a relation between $$x$$ and $$y$$:**
Subtract the two original equations:
$$x^2 - x - (y^2 - y) = 2025y - 2025x$$
$$x^2 - y^2 - x + y = 2025(y - x)$$
Factor:
$$(x - y)(x + y) - (x - y) = 2025(y - x)$$
$$(x - y)(x + y - 1) = 2025(y - x)$$
Note that $$y - x = -(x - y)$$, so:
$$(x - y)(x + y - 1) = -2025(x - y)$$
If $$x \neq y$$, divide both sides by $$x - y$$:
$$x + y - 1 = -2025$$
$$x + y = -2024$$
9. **Check if $$x = y$$:**
If $$x = y$$, substitute into the first equation:
$$x^2 = 2025x + x = 2026x$$
$$x^2 - 2026x = 0$$
$$x(x - 2026) = 0$$
So $$x = 0$$ or $$x = 2026$$.
If $$x = y = 0$$, then $$y^2 = 0$$ and denominator zero in the expression, invalid.
If $$x = y = 2026$$, check second equation:
$$y^2 = 2025x + y$$
$$2026^2 = 2025 \times 2026 + 2026$$
Calculate:
$$2026^2 = 2026 \times 2026$$
$$2025 \times 2026 + 2026 = 2026(2025 + 1) = 2026 \times 2026$$
So it holds.
10. **Calculate the expression for $$x = y = 2026$$:**
$$\frac{x}{y^2} + \frac{y}{x^2} = \frac{2026}{2026^2} + \frac{2026}{2026^2} = 2 \times \frac{2026}{2026^2} = 2 \times \frac{1}{2026} = \frac{2}{2026} = \frac{1}{1013}$$
11. **Calculate the expression for $$x + y = -2024$$ and $$x \neq y$$:**
From step 8, $$x + y = -2024$$.
Rewrite the first original equation:
$$x^2 - x = 2025 y$$
Rewrite as:
$$x^2 - x - 2025 y = 0$$
Similarly for $$y$$:
$$y^2 - y - 2025 x = 0$$
Add these two equations:
$$(x^2 + y^2) - (x + y) - 2025(x + y) = 0$$
$$(x^2 + y^2) - (1 + 2025)(x + y) = 0$$
$$(x^2 + y^2) - 2026(x + y) = 0$$
Use $$x + y = -2024$$:
$$(x^2 + y^2) - 2026(-2024) = 0$$
$$x^2 + y^2 = 2026 \times 2024$$
Recall:
$$(x + y)^2 = x^2 + 2xy + y^2$$
So:
$$x^2 + y^2 = (x + y)^2 - 2xy = (-2024)^2 - 2xy$$
Equate:
$$(-2024)^2 - 2xy = 2026 \times 2024$$
Calculate:
$$2024^2 = 4096576$$
$$2026 \times 2024 = 4101056$$
So:
$$4096576 - 2xy = 4101056$$
$$-2xy = 4101056 - 4096576 = 4480$$
$$xy = -2240$$
12. **Find $$A + B = \frac{x}{y^2} + \frac{y}{x^2}$$:**
Rewrite:
$$\frac{x}{y^2} + \frac{y}{x^2} = \frac{x^3 + y^3}{x^2 y^2}$$
Use:
$$x^3 + y^3 = (x + y)^3 - 3xy(x + y)$$
Calculate numerator:
$$(x + y)^3 - 3xy(x + y) = (-2024)^3 - 3(-2240)(-2024)$$
Calculate:
$$(-2024)^3 = -2024^3$$
Calculate $$2024^3$$:
$$2024^3 = 2024 \times 2024^2 = 2024 \times 4096576 = 8280340224$$
So:
$$(-2024)^3 = -8280340224$$
Calculate:
$$-3(-2240)(-2024) = -3 \times 2240 \times 2024 = -13595520$$
Sum numerator:
$$-8280340224 - 13595520 = -8293935744$$
Calculate denominator:
$$(xy)^2 = (-2240)^2 = 5017600$$
So:
$$A + B = \frac{-8293935744}{5017600} = -1652.8$$ (approx)
13. **Summary:**
- If $$x = y = 2026$$, then $$\frac{x}{y^2} + \frac{y}{x^2} = \frac{1}{1013}$$.
- If $$x + y = -2024$$ and $$xy = -2240$$, then $$\frac{x}{y^2} + \frac{y}{x^2} \approx -1652.8$$.
Since the problem does not specify which solution, the simplest exact value is for $$x = y = 2026$$:
**Final answer:**
$$\boxed{\frac{1}{1013}}$$
Solve Expression 9Ef3F2
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