#1**+2 **

a. This looks to be arithmetic.....common difference between terms =2

And the first term = 2

So

a_{n} = 2 + 2(n - 1) which we can simplify as a_{n} = 2_{n}

b. Also arithmetic .....common difference = 2 ....first term = 3

a_{n} = 3 + 2(n - 1) which we can simplify as a_{n} = 2n + 1

c. Arithmetic....common difference = -25 and the first term is 50

a_{n} = 50 - 25(n - 1) = 75 - 25n

4. Geometric.....common ratio = 1 / (1/3) = 3....first term = 1/3

a_{n} = (1/3)*3^(n - 1)

CPhill Apr 17, 2019