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

 Method (no overloads)

Summary

A power of x times the logarithm of A + B sqrt(Q), for polynomials A,
B and Q, by parts, with the logarithm's derivative written over the conjugate:
with D = A^2 - B^2 Q, it is
D'/(2 D) + (Q (A B' - A' B) + A B Q'/2)/(D sqrt(Q)), a rational function and one over
the root, which the rules for those answer. Rubi's 3.5,
x^3 ln(-1 + 4 x + 4 sqrt((x - 1) x)), where D = 8 x + 1.
https://github.com/asc-community/AngouriMath/issues/233

Remarks

The search differentiates the logarithm as written, a quotient with the root in both
parts, and ran past the budget on what was left. Only for a D that is not a
constant: for one that is, ln(x + sqrt(x^2 + 1)) and the other inverse hyperbolic
functions, the derivative is the root's alone, and the rules for those answer them.
The derivative is an identity of the algebra, sqrt(Q)^2 = Q, with no branch in it.

























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