1. The problem is to evaluate the integral $$\int_0^\pi e^x \cos x \, dx$$.
2. We use integration by parts or recognize this as a standard integral of the form $$\int e^{ax} \cos(bx) \, dx$$.
3. The formula for $$\int e^{ax} \cos(bx) \, dx$$ is:
$$\int e^{ax} \cos(bx) \, dx = \frac{e^{ax}}{a^2 + b^2} (a \cos(bx) + b \sin(bx)) + C$$
4. Here, $$a=1$$ and $$b=1$$, so:
$$\int e^x \cos x \, dx = \frac{e^x}{1^2 + 1^2} (1 \cdot \cos x + 1 \cdot \sin x) + C = \frac{e^x}{2} (\cos x + \sin x) + C$$
5. Evaluate the definite integral from 0 to $$\pi$$:
$$\int_0^\pi e^x \cos x \, dx = \left[ \frac{e^x}{2} (\cos x + \sin x) \right]_0^\pi = \frac{e^\pi}{2} (\cos \pi + \sin \pi) - \frac{e^0}{2} (\cos 0 + \sin 0)$$
6. Substitute values:
$$\cos \pi = -1, \sin \pi = 0, \cos 0 = 1, \sin 0 = 0$$
7. So:
$$= \frac{e^\pi}{2} (-1 + 0) - \frac{1}{2} (1 + 0) = \frac{e^\pi}{2} (-1) - \frac{1}{2} = -\frac{e^\pi}{2} - \frac{1}{2} = -\frac{e^\pi + 1}{2}$$
Final answer:
$$\boxed{-\frac{e^\pi + 1}{2}}$$
Integral Cosine Exponential 66Fa5B
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