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Ch. 8 - Integration Techniques
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Non è quello che usi tu?Cambia libro di testo
Capitolo 8, Problema 8.2.38

9–40. Integration by parts Evaluate the following integrals using integration by parts.
38. ∫ x² ln²(x) dx

Guida verificata passo dopo passo
1
Identify the integral to solve: \(\int x^{2} \ln^{2}(x) \, dx\).
Choose parts for integration by parts. Let \(u = \ln^{2}(x)\) (since its derivative simplifies the expression) and \(dv = x^{2} \, dx\) (which is straightforward to integrate).
Compute \(du\) and \(v\): - Differentiate \(u\): \(du = 2 \ln(x) \cdot \frac{1}{x} \, dx = \frac{2 \ln(x)}{x} \, dx\). - Integrate \(dv\): \(v = \int x^{2} \, dx = \frac{x^{3}}{3}\).
Apply the integration by parts formula: \(\int u \, dv = uv - \int v \, du\). Substitute the expressions: \(\int x^{2} \ln^{2}(x) \, dx = \frac{x^{3}}{3} \ln^{2}(x) - \int \frac{x^{3}}{3} \cdot \frac{2 \ln(x)}{x} \, dx\).
Simplify the integral inside and prepare to solve \(\int \frac{2}{3} x^{2} \ln(x) \, dx\) using integration by parts again, following a similar process.

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