Q. Which recursive formula can be used to define this sequence for n>1?15,28,41,54,67,80,…Choices:(A)a=1427a(B)a=131a(C)a=a+13(D)a=a+a−13
Sequence Type: We have the sequence: 15,28,41,54,67,80,…Is the given sequence geometric or arithmetic?The difference between consecutive terms appears to be constant.The given sequence is likely arithmetic.
Calculate Common Difference: To confirm that the sequence is arithmetic, we calculate the difference between consecutive terms.The difference between the first two terms is 28−15=13.The difference between the second and third terms is 41−28=13.Since the difference is the same, the sequence is indeed arithmetic with a common difference of 13.
Identify Recursive Formula: Now, we need to identify the recursive formula for the given arithmetic sequence.The recursive formula for an arithmetic sequence is generally given by an=an−1+d, where d is the common difference.Substituting the common difference of 13 into the formula, we get an=an−1+13.
Correct Recursive Formula: Looking at the given choices, we can see that the correct recursive formula that matches our calculation is (C) a=a+13. However, the choice should be written more precisely as an=an−1+13.
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