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)
Chandra prakash
if two operators are commute, then result is independent of order..... or.. if two operator commute then they can have simultaneous eigenfuntion or complete set of simulatous eigenfun. or they can be measured simultaneaously arbartry accuratacy....... and for more explanation.. u should study from QM by Griffiths...