How to Find Any Term of a Geometric Sequence

A geometric sequence is a sequence derived by multiplying the last term by a constant. Geometric progressions have many uses in today's society, such as calculating interest on money in a bank account. So if you were wondering how exactly you would work out how much money you'll have in there in a few years, this article will help you find out.

Steps

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    Identify the first term in the sequence, call this number a.
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    Calculate the common ratio (r) of the sequence. It can be calculated by dividing any term of the geometric sequence by the term preceding it.
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    Identify the number of term you wish to find in the sequence. Call this number n. For example, if you wish to find the 8th term in the sequence, then n = 8.
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    The nth term is given by arn-1. Simply insert the values of a, r and n in this formula and evaluate the resulting expression to get the nth term.

Article Info

Categories: Algebra