A series is given by ∑n=1∞1n(n+1)\sum_{n=1}^{\infty} \frac{1}{n(n+1)}∑n=1∞n(n+1)1. Is this geometric?
Yes, r=1r=1r=1
No, it is divergent
No, it is telescoping
Yes, r=1/2r=1/2r=1/2