1. **State the problem:**
We are given the implicit equation $$ue^y = 2x + 8y$$ and asked to find $$\frac{dy}{dx}$$.
2. **Recall the formula and rules:**
Since $$y$$ is a function of $$x$$, we use implicit differentiation. Differentiate both sides with respect to $$x$$, remembering to apply the chain rule for terms involving $$y$$.
3. **Differentiate both sides:**
$$\frac{d}{dx}(ue^y) = \frac{d}{dx}(2x + 8y)$$
4. **Differentiate left side:**
Since $$u$$ is a constant with respect to $$x$$,
$$u \frac{d}{dx}(e^y) = u e^y \frac{dy}{dx}$$ by chain rule.
5. **Differentiate right side:**
$$\frac{d}{dx}(2x) = 2$$ and $$\frac{d}{dx}(8y) = 8 \frac{dy}{dx}$$.
6. **Write the differentiated equation:**
$$u e^y \frac{dy}{dx} = 2 + 8 \frac{dy}{dx}$$
7. **Group terms with $$\frac{dy}{dx}$$ on one side:**
$$u e^y \frac{dy}{dx} - 8 \frac{dy}{dx} = 2$$
8. **Factor out $$\frac{dy}{dx}$$:**
$$\left(u e^y - 8\right) \frac{dy}{dx} = 2$$
9. **Solve for $$\frac{dy}{dx}$$:**
$$\frac{dy}{dx} = \frac{2}{u e^y - 8}$$
10. **Compare with given options:**
None of the options A, B, or C match this derivative exactly, and option D is "هيچيان ن" (none). Therefore, the correct answer is option D.
**Final answer:** $$\frac{dy}{dx} = \frac{2}{u e^y - 8}$$ which corresponds to option D (none of the above).
Implicit Derivative 660A33
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.