Question

Write an expression for the nth term of...
2,1,0,-1...

Answer 1

`a_(n)` = 3 - n

Explanation:

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

1 - 2 = 0 - 1 = - 1 - 0 = - 1

This indicates the sequence is arithmetic with n th term

`a_(n)` = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = 2 and d = - 1 , thus

`a_(n)` = 2 - 1(n - 1) = 2 - n + 1 = 3 - n