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specint(exp(-s*t)*CONST*t^2*bessel_y(1,t),t) wrong #407

Closed rtoy closed 4 months ago

rtoy commented 4 months ago

Imported from SourceForge on 2024-07-02 19:14:00 Created by crategus on 2009-09-26 16:02:30 Original: https://sourceforge.net/p/maxima/bugs/1776

Maxima does not take into a account a constant part of an integrand when doing the Laplace transform of bessel_y(v,a*t) where v is an integer order.

The symbol CONST is missing in the following result:

(%i5) ratsimp(specint(exp(-s*t)*CONST*t^2*bessel_y(1,t),t)); (%o5) (3*s*log((sqrt(s^2+1)+s)/(sqrt(s^2+1)-s))+sqrt(s^2+1)*(2*s^2-4)) /(%pi*sqrt(s^2+1)*(s^4+2*s^2+1))

The error is in the routine f2p105v2cond. The constant part is extracted from the variable l but not multiplied to the result of the Laplace transform.

Dieter Kaiser

rtoy commented 4 months ago

Imported from SourceForge on 2024-07-02 19:14:01 Created by crategus on 2009-09-26 18:53:00 Original: https://sourceforge.net/p/maxima/bugs/1776/#5fbb

Fixed in hypgeo.lisp revision 1.66. Closing this bug report.

Dieter Kaiser

rtoy commented 4 months ago

Imported from SourceForge on 2024-07-02 19:14:03 Created by crategus on 2009-09-26 18:53:03 Original: https://sourceforge.net/p/maxima/bugs/1776/#698e