1. **State the problem:** Evaluate the definite integral $$\int_1^4 x^2 \ln(x) \, dx$$.
2. **Recall the integration by parts formula:**
$$\int u \, dv = uv - \int v \, du$$
3. **Choose parts:** Let
$$u = \ln(x) \implies du = \frac{1}{x} dx$$
$$dv = x^2 dx \implies v = \frac{x^3}{3}$$
4. **Apply integration by parts:**
$$\int_1^4 x^2 \ln(x) \, dx = \left. \frac{x^3}{3} \ln(x) \right|_1^4 - \int_1^4 \frac{x^3}{3} \cdot \frac{1}{x} dx$$
5. **Simplify the integral:**
$$= \left. \frac{x^3}{3} \ln(x) \right|_1^4 - \frac{1}{3} \int_1^4 x^2 dx$$
6. **Evaluate the remaining integral:**
$$\int_1^4 x^2 dx = \left. \frac{x^3}{3} \right|_1^4 = \frac{4^3}{3} - \frac{1^3}{3} = \frac{64}{3} - \frac{1}{3} = \frac{63}{3} = 21$$
7. **Substitute back:**
$$= \left( \frac{4^3}{3} \ln(4) - \frac{1^3}{3} \ln(1) \right) - \frac{1}{3} \times 21$$
8. **Simplify terms:**
Since $$\ln(1) = 0$$,
$$= \frac{64}{3} \ln(4) - 0 - 7 = \frac{64}{3} \ln(4) - 7$$
**Final answer:**
$$\int_1^4 x^2 \ln(x) \, dx = \frac{64}{3} \ln(4) - 7$$
Integral Ln X C2Edda
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