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3 votes
3 votes
Find the nth term for 13 8 3 -2 -7 and the 100th term

User Amol Aggarwal
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1 Answer

9 votes
9 votes

Answer:

see explanation

Explanation:

there is a common difference between consecutive terms in the sequence, that is

8 - 13 = 3 - 8 = - 2 - 3 = - 7 - (- 2) = - 5

this indicates the sequence is arithmetic with nth term


a_(n) = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

here a₁ = 13 and d = - 5 , then


a_(n) = 13 - 5(n - 1) = 13 - 5n + 5 = 18 - 5n

then

a₁₀₀ = 18 - 5(100) = 18 - 500 = - 482

User LemonCool
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