1. **Stating the problem:**
Calculate the limit
$$\lim_{x \to 0} \frac{e^{2x} \sin(x^2) + 2 \cos x - 2 e^{-x^3}}{(\ln(2+x) - \ln 2) \sin(x^2 e^{-x}) \arctan(x + \frac{1}{x})}$$
2. **Analyze the expression:**
We need to evaluate the behavior of numerator and denominator as $x \to 0$.
3. **Approximate each component near 0 using Taylor expansions:**
- $e^{2x} \approx 1 + 2x + 2x^2$
- $\sin(x^2) \approx x^2$
- $\cos x \approx 1 - \frac{x^2}{2}$
- $e^{-x^3} \approx 1 - x^3$
- $\ln(2+x) - \ln 2 = \ln\left(\frac{2+x}{2}\right) = \ln\left(1 + \frac{x}{2}\right) \approx \frac{x}{2}$
- $e^{-x} \approx 1 - x$
- $x^2 e^{-x} \approx x^2 (1 - x) = x^2 - x^3$
- $\sin(x^2 e^{-x}) \approx \sin(x^2 - x^3) \approx x^2 - x^3$
- $\arctan\left(x + \frac{1}{x}\right)$ is not defined at $x=0$ because $\frac{1}{x}$ diverges.
4. **Check the denominator's behavior:**
As $x \to 0$, $x + \frac{1}{x} \to \pm \infty$ depending on the direction, so $\arctan(x + \frac{1}{x}) \to \pm \frac{\pi}{2}$.
5. **Evaluate numerator near 0:**
$$e^{2x} \sin(x^2) \approx (1 + 2x + 2x^2) x^2 = x^2 + 2x^3 + 2x^4$$
$$2 \cos x - 2 e^{-x^3} \approx 2 \left(1 - \frac{x^2}{2}\right) - 2 (1 - x^3) = 2 - x^2 - 2 + 2x^3 = -x^2 + 2x^3$$
Sum numerator:
$$x^2 + 2x^3 + 2x^4 - x^2 + 2x^3 = 4x^3 + 2x^4$$
6. **Evaluate denominator near 0:**
$$(\ln(2+x) - \ln 2) \sin(x^2 e^{-x}) \arctan(x + \frac{1}{x}) \approx \frac{x}{2} (x^2 - x^3) \frac{\pi}{2} = \frac{\pi}{4} (x^3 - x^4)$$
7. **Form the limit expression:**
$$\lim_{x \to 0} \frac{4x^3 + 2x^4}{\frac{\pi}{4} (x^3 - x^4)} = \lim_{x \to 0} \frac{4x^3 + 2x^4}{\frac{\pi}{4} x^3 (1 - x)}$$
8. **Cancel common factors:**
$$= \lim_{x \to 0} \frac{\cancel{x^3} (4 + 2x)}{\frac{\pi}{4} \cancel{x^3} (1 - x)} = \lim_{x \to 0} \frac{4 + 2x}{\frac{\pi}{4} (1 - x)}$$
9. **Simplify denominator fraction:**
$$= \lim_{x \to 0} \frac{4 + 2x}{\frac{\pi}{4} (1 - x)} = \lim_{x \to 0} \frac{4 + 2x}{\frac{\pi}{4} - \frac{\pi}{4} x}$$
10. **Evaluate limit by direct substitution:**
$$= \frac{4 + 0}{\frac{\pi}{4} - 0} = \frac{4}{\frac{\pi}{4}} = 4 \times \frac{4}{\pi} = \frac{16}{\pi}$$
**Final answer:**
$$\boxed{\frac{16}{\pi}}$$
Limit Zero B58Ae9
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