Question

Find an explicit formula for the arithmetic sequence 170,85,0,-85...,
d(n)=

Answer 1

d(n) = 85 * ( 3 - n )

Explanation:

Let's find the common difference of the terms (if any).

The common difference is = 85 - 170 = 0 - 85 = -85 - 0 = -85

For an arithmatic sequence with first term a, common difference d,

nth term = a + ( n - 1 ) * d

So, d(n) = 170 + ( n - 1 ) * (-85)

= 255 - 85n

= 85 ( 3 - n )

[ If there's any mistake, please inform me ]