$$ S = \sum_{n=1}^{\infty}(f_n - f_{n+1}) $$ Define partial sum $S_N = \sum_{n=1}^{N}(f_n - f_{n+1})$. Expanding sigma we obtain: $$ S_N = f_1 - f_2 + f_2 - f_3 + \dots + f_{N} - f_{N+1} = f_1 - f_{N+1} $$

Use tags to organize the notes into categories. First tag is set to be used as a category If you spot something that could be a mistake - start a discussion using comments. If you spot a typo or arithmetic mistake - fill free to fix it immediately. Put problem statements in each category. PDF, PPTX, etc. You can put them here but please don't turn my personal drive into a thrash bin:) Use single note for single exercise if different steps in this exercise are connected, and split exercise into multiple notes otherwise

Gdrive link