MHB Integral involving polylogarithms up to order 4

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The discussion centers on proving the integral involving polylogarithms, specifically the equation that relates the integral of the logarithmic function to polylogarithmic terms. Participants emphasize the importance of understanding polylogarithms for tackling the integral. A hint is provided for those unfamiliar with the concept, suggesting that deeper knowledge of polylogarithms is beneficial for the proof. The conversation reflects a collaborative effort to engage with complex mathematical concepts. The integral's relationship to polylogarithms highlights its significance in advanced calculus.
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Prove the following

$$ \int^x_0 \frac{\log(1+t)\log^2(t)}{t}dt = -\log^2(x) \text{Li}_2(-x)+2 \log(x) \text{Li}_3(-x)-2 \text{Li}_4(-x)$$
 
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ZaidAlyafey said:
Prove the following

$$ \int^x_0 \frac{\log(1+t)\log^2(t)}{t}dt = -\log^2(x) \text{Li}_2(-x)+2 \log(x) \text{Li}_3(-x)-2 \text{Li}_4(-x)$$

I'll not post a direct proof, but for those of you less familiar with the Polylogarithm - and I hope you'll excuse my apparent impertinence here, Zaid - here's a little (optional) hint...(Heidy)(Heidy)(Heidy)
For $$ |Re(z)| \le 1 $$ in the cut plane $$\mathbb{C}-[0, \infty)$$, where the real line ('x' axis) is deleted between $$1$$ and $$\infty$$, the Polylogarithm has the integral representation$$\text{Li}_m(z)=\frac{(-1)^{m+1}}{(m-2)!}\int_0^1\frac{(\log x)^{m-2} \log(1-zx) }{x} \,dx$$ Actually, this definition applies more generally, but the conditions given above ensure that the integral is single-valued, rather than a multi-valued complex function...
My shut up now... :rolleyes::rolleyes::rolleyes:
 
$$ \int_{0}^{x} \frac{\log(1+t) \log^2(t)}{t} \ dt = -\text{Li}_{2}(-t) \log^2 (t) \Big|^{x}_{0} + 2 \int_{0}^{x} \frac{\text{Li}_{2} (-t) \log t}{t} dt $$

$$ = - \text{Li}_{2} (-x) \log^{2} (x) + 2 \Big( \text{Li}_{3}(-t) \log t \Big|^{x}_{0} - \int_{0}^{x} \frac{\text{Li}_{3} (-t)}{t} \ dt \Big)$$

$$ = - \text{Li}_{2} (-x) \log^{2} (x) + 2 \text{Li}_{3}(-x) \log x- 2 \text{Li}_{4}(-x) $$
 
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