Q. Complete the recursive formula of the geometric sequence−0.25,−2,−16,−128,….b(1)=□b(n)=b(n−1)⋅□
Given Sequence: We are given the geometric sequence: −0.25,−2,−16,−128,… To find the recursive formula, we need to determine the common ratio r by dividing any term by its preceding term. Let's divide the second term by the first term: r=(−2)/(−0.25)=8.
Common Ratio: Now that we have the common ratio, we can write the recursive formula. The first term b(1) is given as −0.25. The recursive formula will relate term b(n) to the previous term b(n−1) using the common ratio.The recursive formula is: b(n)=b(n−1)×r, where r=8.
Recursive Formula: Let's verify the recursive formula by applying it to find the third term using the second term.According to the formula, b(3) should equal b(2)×r.We have b(2)=−2 and r=8, so b(3)=−2×8=−16, which matches the given sequence.
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