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As per the title, I evaluated

$$\int\frac{\log(x+a)}{x}\,dx$$

And wanted to make sure my solution is correct, and if not, where I went wrong in my process. Here is my work.

$$\int\frac{\log(x+a)}{x}\,dx$$

$$=\log(a)\int\frac{1}{x}\,dx+\int\frac{\log\left(\frac{x}{a}+1\right)}{x}\,dx$$

For the second integral, let:

$$\frac{x}{a}=u$$

$$=\log(a)\log(x)+\int\frac{\log(1+u)}{u}\,du$$

$$=\log(a)\log(x)-{Li_{2}}\left(-\frac{x}{a}\right)$$

And so

$$\int\frac{\log(x+a)}{x}\,dx=\log(a)\log(x)-{Li_{2}}\left(-\frac{x}{a}\right)$$

Where $Li_{2}(z)$ is the dilogarithm function, and I used:

$$\int\frac{\log(1+z)}{z}\,dz=-Li_{2}(-z)$$

Is this answer correct?

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