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)
Jagat Chaudhary
Dharmasam , both lambda and lambda squares ,used in these questions are constant of integration. you can choose any arbitrary constant as per your choice. This book used lambda square and lambda just to make the solution looks similar to other part. for example , in 1st one, solution is linear type so lambda used , in second question, squares are present so used lambda square. If solution contains some log terms, use log(lambda).
Thank you so much Sir