SOLUTION: How do i write an equation for the nth term of this arithmetic sequence. 7,0,-7,-14,...

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Question 1043001: How do i write an equation for the nth term of this arithmetic sequence.
7,0,-7,-14,...

Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.
How do i write an equation for the nth term of this arithmetic sequence.
7,0,-7,-14,...
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a%5Bn%5D = 7 + (n-1)*(-7), n = 1, 2, 3, . . . 

The first term is 7, the common difference is (-7).

You can simplify the above formula

a%5Bn%5D = 7 - 7(n-1) = 7*(1 - (n-1)) = 7*(2-n), n = 1, 2, 3, . . . 

Now stop asking the same question about each and every AP.

Better read the lesson
    - Arithmetic progressions
in this site.