Write an explicit formula for an, the nth term of the sequence 11,2,-7
1 answer:
Answer:
= 20 - 9n
Step-by-step explanation:
There is a common difference d between consecutive terms, that is
d = 2 - 11 = - 7 - 2 = - 9
This indicates the sequence is arithmetic with nth term
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = 11 and d = - 9 , then
= 11 - 9(n - 1) = 11 - 9n + 9 = 20 - 9n
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