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SolveAPowerOfXTimesAnArctangentAndTheLogarithmOfItsQuadratic​(AngouriMath.​Entity,​AngouriMath.​Entity.​Variable)

 Method (no overloads)

Summary

A whole power of x times F = a + b atan(c x) times G = d + e ln(1 + c^2 x^2),
by parts on the power: with q = c^2 and n = k + 1, the remainder is
(1/n) int x^n (b c G + 2 e q x F)/(1 + q x^2), and x^n/(1 + q x^2) is a
polynomial plus (-1/q)^m x^(n - 2m)/(1 + q x^2), m = floor(n/2).

Remarks

For an odd k the two remainders over the quadratic, G/(1 + q x^2) and
x F/(1 + q x^2), have no elementary antiderivative apiece and come with the same
factor, and together they are (F G)'/(b c) -- F' = b c/(1 + q x^2),
G' = 2 e q x/(1 + q x^2) -- so their integral is that factor times F G.
Integration by parts as the rules after it apply it never pairs them, and Rubi's 5.3.4
x^k (a + b atan(c x))(d + e ln(1 + c^2 x^2)), k = 1 to 4, timed out.
https://github.com/asc-community/AngouriMath/issues/718

























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