Integral X2 E2X
1. We are asked to evaluate the definite integral $$\int_0^1 x^2 e^{2x} \, dx$$.
2. To solve this integral, we use integration by parts. Let:
$$u = x^2 \implies du = 2x \, dx$$
$$dv = e^{2x} \, dx \implies v = \frac{e^{2x}}{2}$$
3. Applying integration by parts formula:
$$\int u \, dv = uv - \int v \, du$$
$$= x^2 \cdot \frac{e^{2x}}{2} - \int \frac{e^{2x}}{2} \cdot 2x \, dx$$
$$= \frac{x^2 e^{2x}}{2} - \int x e^{2x} \, dx$$
4. We now need to evaluate $$\int x e^{2x} \, dx$$. Use integration by parts again:
Let:
$$u = x \implies du = dx$$
$$dv = e^{2x} \, dx \implies v = \frac{e^{2x}}{2}$$
5. Applying integration by parts again:
$$\int x e^{2x} \, dx = x \cdot \frac{e^{2x}}{2} - \int \frac{e^{2x}}{2} \, dx$$
$$= \frac{x e^{2x}}{2} - \frac{1}{2} \int e^{2x} \, dx$$
6. Evaluate $$\int e^{2x} \, dx$$:
$$\int e^{2x} \, dx = \frac{e^{2x}}{2} + C$$
7. Substitute back:
$$\int x e^{2x} \, dx = \frac{x e^{2x}}{2} - \frac{1}{2} \cdot \frac{e^{2x}}{2} + C = \frac{x e^{2x}}{2} - \frac{e^{2x}}{4} + C$$
8. Substitute this result back into step 3:
$$\int_0^1 x^2 e^{2x} \, dx = \left[ \frac{x^2 e^{2x}}{2} - \left( \frac{x e^{2x}}{2} - \frac{e^{2x}}{4} \right) \right]_0^1$$
$$= \left[ \frac{x^2 e^{2x}}{2} - \frac{x e^{2x}}{2} + \frac{e^{2x}}{4} \right]_0^1$$
9. Evaluate at the bounds:
At $$x=1$$:
$$\frac{1^2 e^{2}}{2} - \frac{1 e^{2}}{2} + \frac{e^{2}}{4} = \frac{e^{2}}{2} - \frac{e^{2}}{2} + \frac{e^{2}}{4} = \frac{e^{2}}{4}$$
At $$x=0$$:
$$\frac{0^2 e^{0}}{2} - \frac{0 e^{0}}{2} + \frac{e^{0}}{4} = 0 - 0 + \frac{1}{4} = \frac{1}{4}$$
10. Subtract lower bound from upper bound:
$$\frac{e^{2}}{4} - \frac{1}{4} = \frac{e^{2} - 1}{4}$$
**Final answer:**
$$\int_0^1 x^2 e^{2x} \, dx = \frac{e^{2} - 1}{4}$$