Examples of summation of split term elimination method

Examples of summation of split term elimination method

1. The sum of the first n terms of {1 / [n (n + 1)]};
2. The sum of the first n terms of {1 / (n & sup2; - 1)};
3. The sum of the first n terms of {1 / [n (n + 2)]}
Note: the first one is the simplest sum of split terms, the second one needs splitting, the third one needs splitting and the remaining two terms