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Ch. 8 - Techniques of Integration
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Non è quello che usi tu?Cambia libro di testo
Capitolo 8, Problema 8.6.50

Use reduction formulas to evaluate the integrals in Exercises 41–50.
∫ 16x^3 (ln(x))^2 dx

Guida verificata passo dopo passo
1
Identify the integral to solve: \(\int 16x^{3} (\ln(x))^{2} \, dx\).
Factor out the constant to simplify the integral: \(16 \int x^{3} (\ln(x))^{2} \, dx\).
Use integration by parts, letting \(u = (\ln(x))^{2}\) and $dv = x^{3} dx$. Then compute \(du\) and \(v\): - \(du = 2 \ln(x) \cdot \frac{1}{x} dx = \frac{2 \ln(x)}{x} dx\) - \(v = \frac{x^{4}}{4}\).
Apply the integration by parts formula: \(\int u \, dv = uv - \int v \, du\), so write \(16 \left( \frac{x^{4}}{4} (\ln(x))^{2} - \int \frac{x^{4}}{4} \cdot \frac{2 \ln(x)}{x} dx \right)\).
Simplify the integral inside and recognize that the new integral is \(\int x^{3} \ln(x) \, dx\), which can be solved using the reduction formula or repeated integration by parts.

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