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)
Priyadarshan Choursiya Best Answer
let |G| = 2n+1 for some n€ N. suppose there exist g€G such that |g| = 2. then order of cyclic group || = |g| = 2.
where = {e,g}
by Lagrange's thm, every subgroup divides order of group, so (2n+1)mod2 =0, which is not possible, since 2 doesn't divide odd no.
hence there doesn't exist such g.
therefore G doesn't have any element of order 2.
the proof of Lagrange's thm you understand when you know about costes.