Q. Write an explicit formula that represents the sequence defined by the following recursive formula:a1=3 and an=an−1+7Answer: an=
Identify Terms and Difference: Identify the first term and the common difference from the recursive formula.The first term is given as a1=3. The recursive formula an=an−1+7 indicates that each term is 7 more than the previous term, which means the common difference is 7.
Write Explicit Formula: Use the arithmetic sequence formula to write the explicit formula.The general form of an arithmetic sequence is an=a1+(n−1)d, where a1 is the first term and d is the common difference.
Substitute Values: Substitute the values of a1 and d into the arithmetic sequence formula.a1=3 and d=7, so the explicit formula becomes an=3+(n−1)×7.
Simplify Formula: Simplify the explicit formula.an=3+7n−7an=7n−4
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