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Ch. 7 - Transcendental Functions
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Non è quello che usi tu?Cambia libro di testo
Capitolo 7, Problema 7.6.111

Verify the integration formulas in Exercises 111–114.
111. ∫ (arctan x) / x² dx = ln x - 1/2 ln(1 + x²) - arctan x / x + C

Guida verificata passo dopo passo
1
Identify the integral to verify: \(\int \frac{\arctan x}{x^{2}} \, dx\).
Consider using integration by parts. Let \(u = \arctan x\) and \(dv = \frac{1}{x^{2}} dx\).
Compute the derivatives and integrals needed: \(du = \frac{1}{1 + x^{2}} dx\) and \(v = -\frac{1}{x}\).
Apply the integration by parts formula: \(\int u \, dv = uv - \int v \, du\), which gives \(-\frac{\arctan x}{x} - \int \left(-\frac{1}{x} \cdot \frac{1}{1 + x^{2}}\right) dx\).
Simplify the remaining integral \(\int \frac{1}{x(1 + x^{2})} dx\) by using partial fraction decomposition or substitution, then combine all parts to match the given formula.

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