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)
Anshum Sharma
Here are some handwritten notes from where you can easily understand the concept of direction of planes. If you feel any difficulty, I am there to help you.