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Write an explicit formula for an nth term of the sequence 7, 35, 175,....

User Kkov
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1 Answer

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hello

to write an explicit formula, we have to determine what type of sequence is it

7, 35, 17

this is clearly a geometric progression with values of

first term = 7

common ratio = 5

the explicit formula of a geometric progression is given as


\begin{gathered} a_n=a\cdot r^((n-1))^{} \\ n=\text{nth term} \\ a=\text{first term} \\ r=\text{common ratio} \end{gathered}

now let's substitute the variables into the equation


\begin{gathered} a_n=a\cdot r^((n-1)) \\ a_n=7\cdot5^((n-1)) \\ a_n=35^((n-1)) \end{gathered}

the equation above is the explicit formula for the sequence

User Jimmy Knoot
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