Topic: Electronics Engineering
$T_{r}=r/(1+r^{2}+r^{4})$ $\sum_{1}^{\infty}T_{r}=$
- A. $1/4$
- B. 1
- C. None of the these
- D. $1/2$
Answer: D. $1/2$
Explanation: $T_{r}=\frac{r}{1+r^{2}+r^{4}}$
$\sum_{r=1}^{\infty}T_{r}=\frac{1}{3}+\frac{2}{21}+\frac{3}{91}+\frac{4}{273}+\cdot\cdot\cdot+\infty$
It will converges for the higher values, so the approximate summation upto 4th term is $\sum_{r=1}^{\infty}T_{r}=0.47\mathcal{G}=0.5$