Question

How do you solve this??

Answer 1

`a_n=-(9)/(4) +(1)/(4) *n; \ a_(45)=9.`

Explanation:

1. the difference between two sequent term is: 2- 7/4=7/4 - 3/2 = 3/2 - 5/4=... = 1/4.

2. using the value of the calculated difference it is possible to make up the formula of the given sequence ('n' - the number of term):

`a_n=-(9)/(4)+(1)/(4) n.`

3. for n=45:

`a_(45)=-(9)/(4)+45*(1)/(4)=9.`