Question 1035874: Find the sum of the first 22 terms in the arithmetic series -6 - 12 - 18 - ...
-1,260
-1,518
-1,386
-1,584 Answer by ikleyn(52781) (Show Source):
You can put this solution on YOUR website! Find the sum of the first 22 terms in the arithmetic series -6 - 12 - 18 - ...
-1,260
-1,518
-1,386
-1,584
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Use the formula for the sum of the first n terms of an arithmetic progression
= =
where is the first term, d is the common difference and n is the number of terms (see the lesson Arithmetic progressions in this site).
