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# C2 Series question watch

1. "The sum of the first n terms of a sequence is n(n+2). find the first 3 terms of the sequence"

I have no idea where to begin with this, any ideas?
2. Arithmetic series: find a and d given (n/2)(2(a-1)d) = n(n+2), then the first three terms are straightforward: a, a + d, a + 2d
3. (Original post by shawn_o1)
Arithmetic series: find a and d given (n/2)(2(a-1)d) = n(n+2), then the first three terms are straightforward: a, a + d, a + 2d
Thanks, got it

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