what are the Important books used for JEE MAIN?

Firstly I would suggest you to go through with NCERT Books. Other books you can prefer for JEE Main Preparation given below:

PHYSICS
DC Pandey
HC Verma

CHEMISTRY

O.P Tandon
MATHS
M.L Khanna
R.D Sharma for Trigonometry

Good Luck!

IIT JEE Books  Best Books for Jee Main Physics



BOOKAUTHOR

Concepts of Physics (Part I)HC Verma

Concepts of Physics (Part II)HC Verma

IIT JEE PhysicsDC Pandey

Problems in General PhysicsI.E. Irodov

Physics for IIT-JEEResnick, Halliday, Walker

Problems in PhysicsS.S. Krotov

IIT JEE Books  Best Books for Jee Main Chemistry



BOOKAUTHOR

Organic ChemistryMorrison Boyd

Organic ChemistryO.P Tandon

Modern Approach to Chemical CalculationsR.C. Mukherjee

Numerical ChemistryP. Bahadur

Concise Inorganic Chemistry J.D. Lee

IIT JEE Books   Best Books for Jee Main Mathematics



BOOKAUTHOR

IIT MathematicsM.L. Khanna

Differential CalculusA Das Gupta

Class XI & XII MathematicsR.D. Sharma

Trigonometry, Geometry BooksS.L. Loney

Problems in Calculus of One VariableI.A. Maron

Higher AlgebraHall and Knight