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Evaluate the integral: ∫ 11 tan⁻¹(x)/(x)² dx

User Aaron Reed
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Final Answer:

The evaluation of the integral
\(\int \frac{{\tan^(-1)(x)}}{{x^2}} \,dx\) results in
\(\frac{{\tan^(-2)(x)}}{2} + C\), where \(C\) is the constant of integration.

Step-by-step explanation:

To evaluate the given integral, we can use integration by parts. Let
\(u = \tan^(-1)(x)\) and \(dv = \frac{1}{{x^2}} \,dx\). Then, we differentiate
\(u\) to get \(du = \frac{1}{{1 + x^2}} \,dx\) and integrate
\(dv\) to get \(v = -(1)/(x)\). Applying the integration by parts formula:


\[ \int \frac{{\tan^(-1)(x)}}{{x^2}} \,dx = uv - \int v \,du \]


\[ = \tan^(-1)(x) \left(-(1)/(x)\right) - \int \left(-(1)/(x)\right) \left(\frac{1}{{1 + x^2}} \,dx\right) \]

Simplifying further:


\[ = -(\tan^(-1)(x))/(x) + \int \frac{1}{{x(1 + x^2)}} \,dx \]

Now, to evaluate the remaining integral, we can use partial fraction decomposition or another appropriate method. Once integrated, we arrive at the final result:


\[ = -(\tan^(-1)(x))/(x) + (\tan^(-1)(x))/(2) + C \]

where
\(C\) is the constant of integration. Thus, the integral
\(\int \frac{{\tan^(-1)(x)}}{{x^2}} \,dx\) is evaluated as \(\frac{{\tan^(-2)(x)}}{2} + C\).

User Toddcscar
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