Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Lakshay bhardwaj
you just need to remember the expansion of exp(-x). and compared it with final expansion of series .
thank you for your support
1 small doubt : in 3rd step how (2n+1)! became (2n)!
using property of factorial
u can mark my answer as best answer if u like that ,thank you
actually i tried to convert as best answer. but i couldn't. i don't know y