Q. Complete the recursive formula of the arithmetic sequence−15,−11,−7,−3,….c(1)=□c(n)=c(n−1)+□
Identify common difference: Identify the common difference in the sequence by subtracting any term from the term that follows it. The sequence is −15, −11, −7, −3, ... Subtracting a term from the next term: −11−(−15)=−11+15=4. The common difference, d, is 4.
Write recursive formula: Write the recursive formula using the common difference. The recursive formula for an arithmetic sequence is given by c(n)=c(n−1)+d, where c(n) is the nth term, c(n−1) is the previous term, and d is the common difference. Since we have found that d=4, we can write the recursive formula as c(n)=c(n−1)+4.
Determine first term: Determine the first term of the sequence to complete the recursive formula. The first term, c(1), is given as −15. So, we include this in our recursive formula.
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