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A recursive rule for an arithmetic sequence is a1=-3;an-1+7

What is the iterative rule for this sequence?

A recursive rule for an arithmetic sequence is a1=-3;an-1+7 What is the iterative-example-1
User Sindre J
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1 Answer

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An arithmetic sequence is defined by its first term
a_1
its ratio
r and the defining formula
a_n=r* n+a_1
The first term is given and equal
a_1=-3
The ratio is the difference between two consecutive terms, we compute like this:

a_n=a_(n-1)+7\text{ then } a_n-a_(n-1)=7\\\text{The ratio is the 7}\\\text{The rule is the :}a_n=7n-3

The correct answer is the second one.
User Christian Flem
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