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Integrate a power of a quotient of linears over a half-odd power of their product - #1960

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a-power-of-a-quotient-of-linears-over-a-half-odd-power-of-their-product
Oct 20, 2026
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The parser folds e^(n acoth(a x)) into ((a x + 1)/(a x - 1))^(n/2), a power T^alpha of a quotient of linears. Over a half-odd power of a multiple Q of their product, with a power of x beside it, the antiderivative has Liouville's shape T^alpha P(x) Q^(1/2 - K). Since T'/T = D/((p + q x)(r + s x)), asking F' to equal the integrand gives a three-term recurrence for the coefficients of P. Where the equation past the last one fails, the antiderivative is hypergeometric and the rule declines.

Rubi's 7.4.2 e^(n acoth(a x))/(c - a^2 c x^2)^(3/2) to ^(9/2), and the same beside x, x^2 and x^3, were declined. They are answered now.

Measured on 8a1ef454, branch against master:

Run Problems Master Branch
Pocket: Rubi's 7.3 and 7.4 2,010 1,965 solved 1,975 solved
Family 1, 40 a file 1,381 1,362 1,362
Family 0, whole 1,814 1,789 1,789
Families 2 to 8, sampled 2,410 2,362 2,359

Re-run alone on both builds, 10 of the 13 problems that moved go from declined to answered (7.4.2:858–861, 864, 865, 868–871). The other three are load:

  • 3.2.1:292 and 7.4.1:369 time out on both builds;
  • 7.3.5:50 took master 24 s against a 5 s budget, and other branches' runs have had it going either way.

No run had a wrong answer.

On this master the dispatch line sits after SolveAFunctionOfTheHyperbolicTangent, the last rule of its group. The Moebius rule (#1953) and its tests pass beside it.

APowerOfAQuotientOfLinearsOverAHalfOddPowerOfTheirProductIntegralTest differentiates the answers back. BREAKING-CHANGES.md has the entry, with the 2.5.0 column measured on v2.5.0.

Part of #233.

🤖 Generated with Claude Code

https://claude.ai/code/session_012sonx8iAspMiwRwokT1Ura

…heir product

The parser folds e^(n acoth(a x)) into ((a x + 1)/(a x - 1))^(n/2), a power
T^alpha of a quotient of linears T = (p + q x)/(r + s x). Over a half-odd power
of a multiple Q of their product, with a power of x beside it, the
antiderivative has Liouville's shape T^alpha P(x) Q^(1/2 - K). Since T'/T is
D/((p + q x)(r + s x)), asking F' to be the integrand is a three-term
recurrence for P's coefficients, solved from the bottom up. The last equation
fixes p_0 and the one past it is checked: where it fails, the antiderivative
is hypergeometric and the rule declines. Rubi's 7.4.2
e^(n acoth(a x))/(c - a^2 c x^2)^(3/2) to ^(9/2), and the same beside x, x^2
and x^3, were declined.

Part of #233.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012sonx8iAspMiwRwokT1Ura
@Rafael-SOWNet Rafael-SOWNet added this to the 2.6.0 milestone Oct 20, 2026
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Rafael-SOWNet merged commit a78c1bd into master Oct 20, 2026
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@github-project-automation github-project-automation Bot moved this from Todo to Done in AngouriMath Oct 20, 2026
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Rafael-SOWNet deleted the a-power-of-a-quotient-of-linears-over-a-half-odd-power-of-their-product branch October 29, 2026 00:43
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