It looks like an alternating series, so It’s likely from a physics class involving electrostatic or maybe control systems. It also could be from a later calculus class where you’re first introduced to alternating series like Taylor or Leibniz.

I can’t login with jerboa. Not sure why, but there’s no option to.

I haven’t figured out how to login using Jerboa. There’s no option for me.

Lol

You can tap the 3 dots next to the share button and say you’re not interested in seeing this type of stuff.

You don’t need the /s we all know you’re being sarcastic.