The sum of m terms and n terms of an A.P. ae equal. Prove that the sum of (m+n) terms will be zero. Given that `mnen.`

Explanation

To prove that the sum of (m+n) terms of an A.P. is zero, given that the sum of m terms and n terms are equal, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Given Information**:
We are given that the sum of m terms (S_m) and the sum of n terms (S_n) of an arithmetic progression (A.P.) are equal. Therefore, we can write:
\[
S_m = S_n
...