# Zero check for certain numbers fail

The following zero check yields an error in my copy of Sage (version 9.5):

```
real_part(log(QQbar((-1)^(1/3)))).is_zero()
```

The result of the computation should be `True`

. The entire error message can be found here: https://pastebin.com/iYNjuwZJ
I also checked the Sage Cell Server and the same error appears there. I could not find anything related on the Trac server. However, since I have no idea what is going wrong here, my search was very limited.

From the log it seems that your sage is missing maxima. Could you try to run the command

`maxima(1)`

?`maxima(1)`

works in my installation and gives me a`sage.interfaces.maxima.MaximaElement`

object.Could you give more details about your setup (operating system, how you did install Sage).

I install it by calling

`make`

after cloning form the github repo as described here: https://ask.sagemath.org/question/431... My OS is openSUSE Leap 15.2Then there was probably a problem in the compilation process. If you want a diagnosis you should post the files

`$SAGE_ROOT/config.log`

,`$SAGE_ROOT/config.status`

and possibly the full`$SAGE_ROOT/logs/install.log`

.