Q. Write an explicit formula for an, the nth term of the sequence 5,7,9,…Answer: an=
Identify Sequence Type: Identify whether the given sequence is geometric or arithmetic. The sequence 5,7,9,… has a common difference between consecutive terms, so it is an arithmetic sequence.
Use Explicit Formula: Use the explicit formula for an arithmetic sequence, an=a1+(n−1)d, where a1 is the first term and d is the common difference. For the sequence 5,7,9,…, the first term, a1, is 5 and the common difference, d, is 2.
Substitute Values: Substitute the values of a1 and d into the formula to write an expression to describe the sequence. The expression for the sequence 5,7,9,… is an=5+(n−1)×2.
Simplify Expression: Simplify the expression. an=5+2n−2, which simplifies to an=2n+3.
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