hey,

the syllabus of JEE mains are as follows

for mathematics - sets, relations and functions , complex numbers and quadratic equations , matrices and determinants, permutations and combination , mathematical induction , binomial theorem and its simple applications, sequences and series, limit continuity and differentiability , integral calculus , differential equations, coordinate geometry, three dimensional geometry , vector algebra , statistics and probability , trigonometry , mathematical reasoning

for physics - physics and measurement ,kinematics, laws of motion , work, energy and power , rotational motion , gravitation , properties of solids and liquids , thermodynamics , kinetics theory of gases , oscillations and waves , electrostatics , current electricity , magnetic effects of current and magnetism , electromagnetic induction and alternating currents , electromagnetics waves , optics, dual nature of matter and radiation , atoms and nuclei , electronic devices ,communication systems

for chemistry - some basic concepts in chemistry , states of matter , atomic structure , chemical bonding and molecular structure , chemical thermodynamics, solutions , equilibrium , redox reaction and electrochemistry , chemical kinetics, surface chemistry , classification of elements and periodicity in properties ,general principles and processes of isolation of metals , hydrogen , S- Block elements , P Block elements , D and F block elements , coordination compounds ,environmental chemistry , purification characterisation of organic compounds , some basic principle of organic chemistry , hydrocarbons , organic compounds containing halogens, organic compounds containing oxygen ,alcohols ,phenols and ethers ,carboxylic acids, organic compounds containing nitrogen , polymers , biomolecule, chemistry in every day life , principle related to practical chemistry , chemical principles involved in the following experiments

for more detailed syllabus refer to the link

https://engineering.careers360.com/articles/jee-main-syllabus

for jee mains books https://engineering.careers360.com/articles/best-books-for-jee-main

for neet https://medicine.careers360.com/articles/neet

all the best !

If you are asking about Jee Main and Neet of 2021 session, then I would like to tell you that, CBSE has reduced the syllabus from Class 9 to 12 by 30%. However, NTA has not yet announced any such notification to reduce the syllabus of Jee Main also. But it seems the syllabus of Jee Main and Neet will also be reduced keeping the core concepts unchanged. The topics which carry less weightage may be eliminated from the syllabus of 2020-21 session. The chances are quite high. But until NTA releases any notice, it can't be said properly. Please to hear this from the authority.
NCERT Textbooks are best for basic preparation and concept clarification. Then you can move on to other reference books like HC Verma for Physics, RD sharma for Mathematics, Plane trigonometry by SL Loney, OP Tandon for Chemistry, Truman vol 1 and 2 for Biology.

If this is for Jee Main and Neet 2020, then the syllabus is as follows-

• Biology-

Class XI-
Diversity of Living Organisms 1
Structural Organisation in Plants & Animals
Cell: Structure and Function
Plant Physiology
Human Physiology

Class XII-
Reproduction
Genetics and Evolution
Biology and Human Welfare
Biotechnology and its Applications
Ecology and Environment
http://medicine.careers360.com/articles/neet-syllabus

• Mathematics-

Sets, Relation, Functions, Complex Numbers and Quadratic equations, Matrices and Determinants, Permutations and Combinations, Mathematical Indication, Binomial theorem and its simple applications, Sequences and series, Limit, continuity and differentiability, Integral Calculus, Differential equations, Coordination geometry, 3D geometry, Vector algebra, Statistics and probability, Trigonometry, Mathematical reasoning.

• Physics-

Physical-world and measurement
kinematics
Laws of Motion
Work, Energy and Power
Motion of System of Particles and Rigid Body
Gravitation
Properties of Bulk Matter
Thermodynamics
Behaviour of Perfect Gas and Kinetic Theory
Oscillation & Waves
Electrostatics
Current Electricity
Magnetic Effect of Current & Magnetism
Electromagnetic Induction & Alternating Current
Electromagnetic Waves
Dual Nature of Matter and Radiation
optics
Atoms & Nuclei
Electronic Devices

• Chemistry

Basic Concepts of Chemistry
Structure of Atom
Classification of Elements & Periodicity in Properties
Chemical Bonding and Molecular Structure
States of Matter: Gases and Liquids
Thermodynamics
Equilibrium
Redox Reactions
s-Block Elements
Some p-Block Elements
Organic Chemistry: Basic Principles & Techniques
Hydrocarbons
Environmental Chemistry
Solid State
Solutions
Electrochemistry
Chemical Kinetics
Surface Chemistry
Isolation of Elements
p-Block Elements
d- and f-Block Elements
Coordination Compounds
Haloalkanes and Haloarenes
Alcohols, Phenols and Ethers
Aldehydes, Ketones and Carboxylic Acids
Organic Compounds containing Nitrogen
Biomolecules
Polymers
Chemistry in Everyday Life

http://engineering.careers360.com/articles/jee-main-syllabus

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