# solve x*exp(x)==0 and x*exp(-x)==0

```
sage: solve(x*exp(x)==0,x)
[x == 0, e^x == 0]
```

but

```
sage: solve(x*exp(-x)==0,x)
[x == 0]
```

How can i avoid the e^x==0 in the solutionlist?

Thanks for help.

solve x*exp(x)==0 and x*exp(-x)==0

```
sage: solve(x*exp(x)==0,x)
[x == 0, e^x == 0]
```

but

```
sage: solve(x*exp(-x)==0,x)
[x == 0]
```

How can i avoid the e^x==0 in the solutionlist?

Thanks for help.

0

This should be fixed in Sage 5.0, because of Trac 10682. Compare the following (old and new versions of Maxima):

```
Maxima 5.23.2 http://maxima.sourceforge.net
using Lisp ECL 11.1.1
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i1) solve(x*%e^x=0,x);
x
(%o1) [x = 0, %e = 0]
Maxima 5.26.0 http://maxima.sourceforge.net
using Lisp SBCL 1.0.24
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i2) solve(x*%e^x=0,x);
(%o2) [x = 0]
```

Asked: **
2012-03-12 02:06:03 -0500
**

Seen: **312 times**

Last updated: **Mar 12 '12**

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In Maxima 5.26.0 both solutions are [x=0] so I hope the problem will vanish soon

Huh, identical timings! Yes, #10682 should take care of it, and has positive review.