0 votes 0 votes The value of the series $\sum _{n=1}^{\infty }\frac{n}{2^{n}}$ is $1$ $2$ $3$ $4$. TIFR tifrmaths2016 + – soujanyareddy13 asked Aug 30, 2020 • edited Oct 1, 2020 by soujanyareddy13 soujanyareddy13 177 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.