[Maxima] changevar bug?

Richard Hennessy rich.hennessy at verizon.net
Thu Sep 17 22:25:24 CDT 2009

```Never mind.  If you say kill(all) first it works fine.

Rich

----- Original Message -----
From: "Richard Hennessy" <rich.hennessy at verizon.net>
To: "Maxima List" <maxima at math.utexas.edu>
Sent: Thursday, September 17, 2009 9:57 PM
Subject: [Maxima] changevar bug?

I am not sure of why but this used to work in Maxima 5.18.1.

(%i1) assume(E[n]>0,mu>0,m>0,n>0)\$

(%i2) sqrt(2)*sqrt(m)*'integrate(sqrt(E[n]-mu*x^4),x,-E[n]^(1/4)/mu^(1/4),E[n]^(1/4)/mu^(1/4))=%pi*hbar*(n-1/2)\$

(%i3) changevar (%,z-(mu/E[n])^(1/4)*x, z, x);
->> 0=%pi*hbar*(n-1/2)

This is wrong, in 5.18.1 I used to get

(%i3 changevar (%,z-(mu/E[n])^(1/4)*x, z, x);
->> (sqrt(2)*sqrt(m)*E[n]^(3/4)*integrate(sqrt(1-z)*sqrt(z+1)*sqrt(z^2+1),z,-1,1))/mu^(1/4)=%pi*hbar*(n-1/2)

Rich

_______________________________________________
Maxima mailing list
Maxima at math.utexas.edu
http://www.math.utexas.edu/mailman/listinfo/maxima

```