Write an equation to describe the sequence below. Use n to represent the position of a term in the sequence, where n=1 for the first term.9,18,36,…Write your answer using decimals and integers.an=_____(_____)n−1
Q. Write an equation to describe the sequence below. Use n to represent the position of a term in the sequence, where n=1 for the first term.9,18,36,…Write your answer using decimals and integers.an=_____(_____)n−1
Identify sequence type: Identify the type of sequence.The sequence is 9,18,36,… where each term appears to be twice the previous term. This suggests that the sequence is geometric.
Determine first term and ratio: Determine the first term (a1) and the common ratio (r).The first term a1 is the first number in the sequence, which is 9.To find the common ratio r, we divide the second term by the first term: r=918=2.
Write nth term formula: Write the formula for the nth term of a geometric sequence.The nth term an of a geometric sequence is given by the formula an=a1⋅r(n−1).
Substitute values into formula: Substitute the values of a1 and r into the formula.We have a1=9 and r=2, so the formula becomes an=9×2(n−1).
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