How do you solve this??
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Answer:
[tex]a_n=-\frac{9}{4} +\frac{1}{4} *n; \ a_{45}=9.[/tex]
Step-by-step 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):
[tex]a_n=-\frac{9}{4}+\frac{1}{4} n.[/tex]
3. for n=45:
[tex]a_{45}=-\frac{9}{4}+45*\frac{1}{4}=9.[/tex]