Dear Snehal,

The syllabus is very vast. As both years, eleventh and twelfth are asked in the examination, a little presence of mind along with rigorous practice of previous years papers will help you in cracking the paper. 

The syllabus includes advanced algebra, trigonometry, analytical mathematics, differential calculus, two dimensional and three dimensional geometry, integral calculus and vectors. You can choose your strong chapters and hone them to perfection. Because in IIT-jee knowing everything about something is more beneficial than knowing something of everything. 

Trigonometry is generally required in other parts of JEE and there are hardly any pure Trigonometry questions asked in JEE. I would recommend to study and practice this section during the early stages of JEE preparation. Also, please memorize the important Trigonometry formulas, as they are used extensively.

Now, Calculus is the most scoring section of all of Mathematics for JEE. Calculus involves a little but of formula/trick memorizations, and lots of practice. I have seen even average students scoring full in Calculus part. All this section involves is some brain work, and practice.

Algebra is a section which takes up a lot of time, but usually doesn't give comparatively better results. However, this doesn't mean you can ignore this section. This section in total constitute of nearly 40% of JEE Mathematics. Take this section very seriously, and try to wrap it up asap.

Similarly, Vector and 3D Geometry are also very-very scoring. It involves only a few type of questions, however put forward in a different style. This is according to me the most easy section of JEE, and constitute nearly 25% weightage of JEE Mathematics. Don't take this section lightly and practice it as much as possible.

Coordinate Geometry involves memorizing lots and lots of formulas. You would need to practice a variety of questions and devote a lot of time in practicing to this chapter. Circles is the most important part of this section.

Probability and Statistics is the toughest part of JEE Mathematics. It need to be understood well, conceptually and practically. Understanding of theorems and their right implementation is very important in this section.

To score good marks in mathematics section you need to do lot of practice. Make sure your basics are clear.

MTG is good book for your practice. Make sure you also solve previous year papers to understand the exam pattern and leval of questions. Work on your speed as well you can solve MCQs and timing test as well.

Good luck!!