My problem is that I don't know how to make it accept spaces in the command to be run. This works:

    ipython3 --InteractiveShellApp.exec_lines='["print(2)"]'

This does not work:

    ipython3 --InteractiveShellApp.exec_lines='["from math import *"]'

The latter command results in the following error:

    [TerminalIPythonApp] CRITICAL | The 'exec_lines' trait of a TerminalIPythonApp instance must be a list, but a value of class 'str' (i.e. '["from') was specified.

Rather than fiddling around with quoting bash, you can put the import line in a startup file: http://ipython.readthedocs.io/en/stable/interactive/tutorial...

idk, it works for me:

    $ ipython3 --InteractiveShellApp.exec_lines='["from math import *"]'
    Python 3.6.5 |Anaconda, Inc.| (default, Apr 26 2018, 08:42:37)
    Type 'copyright', 'credits' or 'license' for more information
    IPython 6.4.0 -- An enhanced Interactive Python. Type '?' for help.

    In [1]: sin(5)
    Out[1]: -0.9589242746631385

I see. I have iPython 5.1.0. Maybe there was a bug that has been fixed in yours.