1. **Problem:** Evaluate the integral $$\int t e^{-2t} \, dt$$
2. **Formula and method:** Use integration by parts where $$u = t$$ and $$dv = e^{-2t} dt$$.
3. **Calculate derivatives and integrals:**
$$du = dt$$
$$v = \int e^{-2t} dt = \frac{e^{-2t}}{-2} = -\frac{1}{2} e^{-2t}$$
4. **Apply integration by parts formula:**
$$\int u \, dv = uv - \int v \, du$$
5. **Substitute:**
$$\int t e^{-2t} dt = t \left(-\frac{1}{2} e^{-2t}\right) - \int \left(-\frac{1}{2} e^{-2t}\right) dt$$
6. **Simplify:**
$$= -\frac{t}{2} e^{-2t} + \frac{1}{2} \int e^{-2t} dt$$
7. **Integrate remaining integral:**
$$\int e^{-2t} dt = -\frac{1}{2} e^{-2t}$$
8. **Substitute back:**
$$= -\frac{t}{2} e^{-2t} + \frac{1}{2} \left(-\frac{1}{2} e^{-2t}\right) + C = -\frac{t}{2} e^{-2t} - \frac{1}{4} e^{-2t} + C$$
9. **Final answer:**
$$\boxed{-\frac{t}{2} e^{-2t} - \frac{1}{4} e^{-2t} + C}$$
Integral Te^ 2T 6475Aa
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