Could someone please check my work I'm only allowed to use the provided definition

Please state all definitions and theorems that you will need: Definition 5.1.1 Let f: D - R and letc be an accumulation point of D. We say that a real number L is a limit of f at c , if for each & > 0 there exists a o > 0 such that If(x) - L| 0 361, 62 > 0 such that 0 0. Since c is an accumulation point of D , there exists an a E D such that 0