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Find a formula for the nth termof the arithmetic sequence.First term 9Common difference -2an = [? ]n + []

User Hamdog
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1 Answer

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Given:

First term 9

Common difference -2

Required:

Find a formula for the nth term of the arithmetic sequence.

Step-by-step explanation:

The general formula for the nth term of the an arithmetic sequence is given by the formula:


a_n=a+(n-1)d

Where a = first term

d = common difference

Put a = 9 and d = -2 in the formula.


\begin{gathered} a_n=9+(n-1)(-2) \\ a_n=9-2(n-1) \\ a_n=9-2n+2 \\ a_n=-2n+11 \end{gathered}

Final Answer:

The nth term of the arithmetic sequence is


a_n=-2n+11

User Mrvncaragay
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