Q. Write an explicit formula for an, the nth term of the sequence 144,24,4,…Answer: an=
Identify Sequence Type: Identify whether the given sequence is geometric or arithmetic. The sequence 144, 24, 4, ... has a common ratio between consecutive terms, so it is a geometric sequence.
Use Explicit Formula: Use the explicit formula for a geometric sequence, an=a1×r(n−1), where a1 is the first term and r is the common ratio. For the sequence 144,24,4,…, the first term, a1, is 144 and the common ratio, r, can be found by dividing the second term by the first term: r=14424=61.
Substitute Values: Substitute the values of a1 and r into the formula to write an explicit formula for the nth term of the sequence. The expression for the sequence 144,24,4,… is an=144×(1/6)n−1.
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