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

 Method (no overloads)

Summary

A power of x times a whole power of its logarithm, x^p ln(x)^n, by the
closed reduction
x^(p + 1) sum_(k = 0..n) (-1)^k n!/(n - k)! ln(x)^(n - k)/(p + 1)^(k + 1), for
any p but -1, where it is ln(x)^(n + 1)/(n + 1). And the same
for F = A + B ln(c x^r) in the logarithm's place, whose derivative is
s/x for s = B r: each step of parts brings a factor s, so the
sum is over (-s)^k n!/(n - k)! F^(n - k)/(p + 1)^(k + 1), and at p = -1 it is F^(n + 1)/((n + 1) s). Rubi's (e x)^q (a + b ln(c x^n))^3, and
t^(-2 - m) (A + B ln(e t^n))^2 in the variable of the quotient substitution.

Remarks

By parts n times, written out: each step takes one from the power of the
logarithm and divides by p + 1. Timofeev's x^m ln(x)^2 and
ln(x)^2/x^(5/2) had no antiderivative -- the first step of by parts was
taken and the second, on x^m ln(x) with the symbol still in the exponent,
was not -- where x^m ln(x) and x^2 ln(x)^2 were answered. Closed, exact,
and volunteered at any depth.
https://github.com/asc-community/AngouriMath/issues/718

























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