For a sequence a 1 a 2 a 3. Then multiply 73 21. Part B Write an explicit formula to represent the number of.
The first term of the sequence.
In a geometric sequence where the ratio of the given term is constant to the previous term the recursive formula is expressed as. A n. We double 1 to get 2 then take that result of 2 and apply double again to get 4 then take the 4 and double it to get 8 and so on. So for n4 first use the equation f n 12 - 7 n - 1 plug in 4 for n.