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Use the explicit formula to find a recursive formula for the sequence aa. Write your answer in simplest form. The recursive formula should depend on aa. \newlinea=19n40a = -19n - 40\newlinea = ______

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Q. Use the explicit formula to find a recursive formula for the sequence aa. Write your answer in simplest form. The recursive formula should depend on aa. \newlinea=19n40a = -19n - 40\newlinea = ______
  1. Identify Sequence Type: Identify if the given sequence is geometric or arithmetic.\newlineThe explicit formula a=19n40a = -19n - 40 involves a linear term in nn without any exponents, which indicates that the sequence is arithmetic.
  2. Find First Term: Find the first term of the sequence using the explicit formula.\newlineTo find the first term, substitute n=1n = 1 into the explicit formula:\newlinea1=19(1)40a_1 = -19(1) - 40\newlinea1=1940a_1 = -19 - 40\newlinea1=59a_1 = -59
  3. Find Second Term: Find the second term of the sequence using the explicit formula.\newlineTo find the second term, substitute n=2n = 2 into the explicit formula:\newlinea2=19(2)40a_2 = -19(2) - 40\newlinea2=3840a_2 = -38 - 40\newlinea2=78a_2 = -78
  4. Find Common Difference: Find the common difference in the arithmetic sequence.\newlineThe common difference dd can be found by subtracting the first term from the second term:\newlined=a2a1d = a_2 - a_1\newlined=78(59)d = -78 - (-59)\newlined=78+59d = -78 + 59\newlined=19d = -19
  5. Write Recursive Formula: Write the recursive formula by plugging in the value of the common difference.\newlineThe recursive formula for an arithmetic sequence is an=an1+da_n = a_{n - 1} + d. Substitute 19-19 for dd in the formula:\newlinean=an119a_n = a_{n - 1} - 19

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