there are so many videos about this topic on youtube its insane, if you are/used to be a math head you probably heard of 3Blue1Brown's videos, he covers this topic like at least 3 times through what i think was the span of 5 years, it may seem purely algebraic but it also has some beautiful geometric proofs too, like this one! https://www.youtube.com/watch?v=-dhHrg-KbJ0
CapCat5318
there are so many videos about this topic on youtube its insane, if you are/used to be a math head you probably heard of 3Blue1Brown's videos, he covers this topic like at least 3 times through what i think was the span of 5 years, it may seem purely algebraic but it also has some beautiful geometric proofs too, like this one! https://www.youtube.com/watch?v=-dhHrg-KbJ0