Answer:
an = 5/2 +3/2(n -1)
Explanation:
The common difference is ...
4 -5/2 = 3/2
The general rule is ...
an = a1 +d(n -1)
For a1 = 5/2 and d = 3/2, the rule for this sequence is ...
an = 5/2 +3/2(n -1)
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This can be simplified to ...
an = 1 +3/2n