1) A series is called finite, if there is a finite number of factors that need to be added. If there are infinitely many factors (after any finite number of additions, there are still factors to add), then it is called infinite.
2) We have that this is the sup of powers of 2; but it does not take all powers of 2, only until the 8th power of 2. Hence, there are 8 summants, a finite number.
3) We have that this series involves all the natural numbers; "..." means that we should continue adding the next term, meaning that there is no end.
4) In order to find the first term of the series, we need to substitute n=1. Hence the first term is 1/(2*1+1)=1/3. Similarly, the next term is equal to 2/(2*2+1)=2/5
5) We notice that the first term is 2 and then that all the terms are 2 higher than their previous one. Hence we have that if we start summation from 1, we need to double it to get the term. This works for all and hence we have that the series is equal to: [tex]\sum_{n=1 \ n=6} 2n[/tex].
6) We have that after one, year, he gains 4%*2000, hence the final amount is 1.04*2000 after one year. Next year, this becomes the capital and we have to multiply again by 1.04. Hence, after 5 years, the total annuity value is: (1.04)^5*2000=2433$.
7) We have that the sum is 4+7+... up until 3*12+1=37. The sum of those is 246 or else we can have that it is equal to 3* n(n+1)/2+12 where n=12 (The sum of all numbers from 1 to n is given by n*(n+1)/2 )
