Q. Let $a_{n}$ be the nth term of an A.P. If $\displaystyle\sum_{r=1}^{100} a_{2 r}=\alpha$ and $\displaystyle\sum_{r=1}^{100} a_{2 r-1}=\beta$, and the common difference of A.P. is $\frac{\alpha-\beta}{\lambda}$ then find $\lambda$.
Sequences and Series
Solution:
