d represents the common difference.....and since the common difference is 3, u have to add 3 to each term to find the next term....because with an arithmetic sequence u add to find the next term, whereas, in a geometric sequence u multiply to find the next term
5...first term 5 + 3 = 8...2nd term 8 + 3 = 11...3rd term 11 + 3 = 14...4th term
