+1−1+1−1+... Explained in 5 Levels from Algebra to Math Major

What is +1−1+1−1+...? Let's explore this series in 5 levels, ranging from explorations with arithmetic and algebra to rigorous solutions from Calculus and beyond! 00:00 Introduction 00:18 Level 1 -- Arithmetic Ideas 01:33 Level 2 -- Algebra Ideas 03:01 Level 3 -- Calculus 04:01 Level 4 -- Cesàro Sum 05:20 Level 5 -- Abel Sum