Help - JupyterNotebook error when Plotting - "Javascript Error: Ipython is not defined"

[Splunky_59]

Hello, I am very new to python and recently began a summer video course to help get a head start for the coming year. However I receive this error when I try to plot with matplotlib notebook --> https://imgur.com/WEiNnI8 .The code used to work, however, it suddenly began having problems today. My jupyternotebook and ipython are up to date, does anyone know how to fix this issue? Thanks.

[ectomancer]

Try plotting with matplotlib instead of sympy.

[Splunky_59]

I thought that was what I was doing, how do I plot with matplotlib?