Question

Find the first 5 partial sums of the series ∑n=2 to ∞ 1/(n(n+4))?

I got 1/12 for the first one but when I put 1/21 for the next one it says it's wrong please help

Answer 1

1/21 is just the 2nd term in the sequence, but is not a partial sum

S1 = 1/12
S2 = 1/12 + 1/21 = 11/84
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