There are pairs of rational numbers $(a,b)$

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There are pairs of rational numbers $(a,b)$, $a<b$, such that $\int^b_a \frac{(2x-5)^{2020}}{x+1} \,dx \in \mathbb Q$ I do not know what to do here. I really have no idea and I am sorry for that. Could you help me, please?

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$$\frac{(2 x-5)^{2020}}{x+1}=p_{2019}(x)+(-7)^{2020}\cdot \frac{1}{x+1}$$ integrating on $[a,b]$ we get $$P_{2020}(b)-P_{2020}(a)+(-7)^{2020}\log\frac{b+1}{a+1}$$ the unique values that make this result a rational number are $a=b$. For any rationals $a,b$ such that $a\ne b$ we have $\log\frac{b+1}{a+1}$ irrational, transcendental to be more precise.

Therefore there is no rationals $a<b$ such that the given integral is rational