Could someone please help me with this problem

Prove Corollary 5.1.9: If f: D - R and if c is an accumulation point of D , then f can have only one limit at c . 2. by using Theorems 5.1.8 and 4.1.14. Theoren 5.1.8 Let F:D-R and let c be an accumulation point of D. Then lim fc)= Liff for every sequence ( sn) in D That converges To C *> C I with Sat c for all n, The sequence ( f( SA)) converges To L. 20 pts 1 Theorem 4.1.14 If a sequence converges, its limit is unique