I have a math assignment here dealing with geometric series/sequences, arithmetic series/sequences, and the recursion formula. The problem is that I don't know which formula applies to which question!
If you could, a detailed explanation would be really wonderful.
Here are the questions:
1. Find and for the sequence
(For this one, I use the geometric sequence, right?)
2. Find for
3. Each year, for 8 years, the population of a city increased by 3.5% of its value in the previous year. If the initial population was 320 000, what was its population by the end of the 8th year?
4. If a sequence is determined by where is a natural number, find the sum of the first 15 terms.
Of course I don't expect anyone to help me with all of them, but even if you helped me figure out which formula to use for any of them, I would be really grateful!
Thank you so much in advance!