SolveByExpandingAProductOfSums​(AngouriMath.​Entity,​AngouriMath.​Entity.​Variable,​System.​Boolean)

(a + b x^n)(c + d x^n)^3 had no antiderivative, and written out it is eight
powers of x, each answered at once: no rule reads a power of x whose exponent is a
symbol as a polynomial, and the rule above writes out one power and not a product of
them. As late as that one, and for the same reason: a product that a rule answers in
its own terms is not written out. Only where every factor with x in it is a sum of
powers of x, a positive whole power of one, or a power of x itself, so that writing it
out is a finite identity, bounded by MaxExpansionTermCount,
whose terms are each answered at once; and only for the question asked, not for what a
rule leaves over. A sum of exponentials is a sum too: integration by parts on
x^2 Shi(a + b x) sinh(a + b x) leaves a run of them beside powers of x, and
written out each term is a search of its own.
https://github.com/asc-community/AngouriMath/issues/718