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)
Ruby negi
vector algebra help u in EMT(u can do vector algebra from first chapter of Griffiths), matrix ,complex help u in Quantum Physics , residue of complex analysis is most important. Taylor series is evergreen,used everywhere. Differential equations help u in every part of Physics for finding the solution of equations. Fourier series too help in Quantum Physics, Fourier series important one help u in Quantum, statistical Physics... for these topics u can do HK dass(simplest book), Arfken . and for online sources, u can watch nptel lectures..