u/nuggies4lifee7

i was just using my sci calc during my free time and i stumbled upon the Σ symbol

heres the photo of the equation

i know little to nothing about calculus as a middle schooler so i just wanna know what the thing does and why the answer ended up like that

(equation is in the next slide)

I'm new to desmos and I just wanna know why the graph ended up like this. Not saying I was trying to do something else since I was just testing out some trig functions

I'm actually saying this as someone who knows barely anything about trigonometry so I'm sorry if this question came off as a bit stupid 😔