[Maxima-bugs] [maxima:bugs] #4572 integration with subs of the form y = exp(X)

[Barton W. <wil...@us...>]

- **status**: open --> closed
- **Comment**:

Fixed by Commit [2d92a1] master.  Appended test suggested in bug report. I ma closing this ticket.



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**[bugs:#4572] integration with subs of the form y = exp(X)**

**Status:** closed
**Group:** None
**Labels:** integrate 
**Created:** Fri Jun 20, 2025 09:55 PM UTC by Barton Willis
**Last Updated:** Fri Jun 20, 2025 09:55 PM UTC
**Owner:** nobody


The integration code attempts to find a substitution of the form `y = exp(X)` that "works."  But the method is rather weak--if the substitution doesn't work, the code doesn't try to find another .  

Here is an example that works out  OK--it tries the substitution `y=exp(x+1)`
~~~
(%i1)	integrate((1 + exp(x+1) + exp(2*x+1))^(1/2),x);
(%o1)	(sqrt(%e)*asinh((2*%e^x+1)/sqrt(4*%e^(-1)-1)))/2-asinh((2*%e^(-x-1))/sqrt(4*%e^(-1)-1)+1/sqrt(4*%e^(-1)-1))+sqrt(%e^(2*(x+1)-1)+%e^(x+1)+1)
~~~

But  this case isn't--here it tries the substitution `y = exp(2 x)` and gives up:
~~~
(%i2)	integrate((1 + exp(x+14) + exp(2*x))^(1/2),x);
(%o2)	integrate(sqrt(%e^(x+14)+%e^(2*x)+1),x)
~~~
This is more of a deficiency than a bug, but it is stopping my progress toward fixing a but in `ordmexpt`


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