Question

Consider the arithmetic sequence 10, 8, 6, 4, ....

What is an expression in terms of n for the nth number in the sequence?

Answer 1

12-2n

Explanation:

Answer 2

12 - 2n

Explanation:

The n th term of an arithmetic sequence is

`a_(n)` = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = 10 and d = 8 - 10 = - 2, thus

`a_(n)` = 10 - 2(n - 1) = 10 - 2n + 2 = 12 - 2n