If a = 1/2! + ^2C2/3! + ^3C2/4! + ^4C2/5! + .....

Question

If \(a = \frac {1}{2!}+ \frac {^2C_2}{3!} + \frac {^3C_2}{4!} + \frac {^4C_2}{5!} + ...\)

\(b = 1 + \frac {^1C_0 + ^1C _1}{1!} + \frac {^2C_0 + ^{+2}C_1 + ^2C_2}{2!} + ...\)

Then \(\frac {2b}{a^2}\) equals to

Answer 1

Correct answer is : 8