Perform Substitution: Let I=∫x+1xdx. To solve this integral, we will perform a substitution. Let u=x+1, which implies that du=dx and x=u−1.
Rewrite in terms of u: Rewrite the integral in terms of u. The integral becomes I=∫uu−1du.
Simplify Integral: This integral does not have a straightforward antiderivative, so we will try to simplify it further. We can split the integral into two parts using the property of integrals that ∫f(x)+g(x)dx=∫f(x)dx+∫g(x)dx. However, in this case, it does not seem to simplify the problem. We need to find another approach.
Attempt Integration by Parts: Since the direct approach does not simplify the integral, we will try integration by parts. However, this also does not seem to lead to a simplification because we do not have a product of functions that would be suitable for integration by parts. We need to find a different method.
Try Another Substitution: We will attempt a different substitution to simplify the integral. Let's try the substitution x=t2, which implies that dx=2tdt and x=t.
Rewrite in terms of t: Rewrite the integral in terms of t. The integral becomes I=∫t2+1t⋅2tdt=2∫t2+1t2dt.
Split Integral into Two Parts: Now we can split the integral into two parts: 2∫(t2+1t2+1−1)dt=2∫1dt−2∫t2+11dt.
Integrate Separately: Integrate both parts separately. The first part is straightforward: 2∫1dt=2t. The second part is a standard integral: 2∫t2+11dt=2arctan(t).
Combine Results: Combine the results of the two integrals. I=2t−2arctan(t)+C, where C is the constant of integration.
Substitute back for t: Substitute back for t to get the integral in terms of x. Since t=x, we have I=2x−2arctan(x)+C.
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