Q. Write an explicit formula that represents the sequence defined by the following recursive formula:a1=144 and an=61an−1Answer: an=
Identify first term and formula: Identify the first term and the recursive formula.The first term is given as a1=144. The recursive formula is given as an=61an−1, which means each term is one-sixth of the previous term.
Recognize sequence type: Recognize the type of sequence. Since each term is a constant fraction of the previous term, this is a geometric sequence.
Determine common ratio: Determine the common ratio r of the geometric sequence.The common ratio r is the factor that each term is multiplied by to get the next term. From the recursive formula, r=61.
Write explicit formula: Write the explicit formula for a geometric sequence.The explicit formula for a geometric sequence is an=a1×r(n−1), where a1 is the first term and r is the common ratio.
Substitute values into formula: Substitute the values of a1 and r into the explicit formula.a1=144 and r=61, so the explicit formula becomes an=144×(61)n−1.
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