Question

$\frac{1}{2!} + \frac{1 + 2}{3!} + \frac{1 + 2 + 3}{4!} + ......\infty =$

• A. $e$
• B. $2e$
• C. e/2
• D. None of these

Answer 1

Answer: (C)

e/2

Answer 2

$\frac{1}{n} - \frac{1}{2n^{2}} + \frac{1}{3n^{3}} - \frac{1}{4n^{4}} + ....$

Here $\log_{e}\left( \frac{n + 1}{n} \right)$

$\log_{e}\left( \frac{n}{n + 1} \right)$.