1. **Problem:** Prove that $$\frac{dy}{dx} = x^{\sin x - 1} \left( \sin x + x \cos x \ln x \right)$$ is the derivative of $$y = x^{\sin x}$$.
2. **Formula and rules:** For functions of the form $$y = u^v$$ where both $$u$$ and $$v$$ depend on $$x$$, use logarithmic differentiation:
$$\ln y = v \ln u$$
Differentiate both sides using the product and chain rules:
$$\frac{1}{y} \frac{dy}{dx} = \frac{dv}{dx} \ln u + v \frac{1}{u} \frac{du}{dx}$$
3. **Apply to given function:**
Let $$y = x^{\sin x}$$, so $$u = x$$ and $$v = \sin x$$.
4. **Differentiate:**
$$\ln y = \sin x \cdot \ln x$$
Differentiate both sides:
$$\frac{1}{y} \frac{dy}{dx} = \cos x \ln x + \sin x \cdot \frac{1}{x}$$
5. **Solve for $$\frac{dy}{dx}$$:**
$$\frac{dy}{dx} = y \left( \cos x \ln x + \frac{\sin x}{x} \right) = x^{\sin x} \left( \cos x \ln x + \frac{\sin x}{x} \right)$$
6. **Rewrite expression:**
Multiply inside the parentheses by $$\frac{x}{x}$$ to get a common denominator:
$$x^{\sin x} \cdot \frac{x \cos x \ln x + \sin x}{x} = x^{\sin x - 1} \left( \sin x + x \cos x \ln x \right)$$
7. **Conclusion:**
Thus, the derivative is
$$\frac{dy}{dx} = x^{\sin x - 1} \left( \sin x + x \cos x \ln x \right)$$
which matches the given expression.
Final answer: $$\boxed{\frac{dy}{dx} = x^{\sin x - 1} \left( \sin x + x \cos x \ln x \right)}$$
Derivative X Sinx 2763A3
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