No, you can not cheat in JEE Mains. This exam is conducted under high security. Moreover JEE Mains will be conducted in online or computer based mode, which makes use of secured IT Softwares which prevents the leaking of question papers. Candidates appearing for JEE Mains will undergo security check at the entrance of the Examination Centre. If candidate wearing shoes and shocks has to open and get it checked by security to prevent any kind of cheating in exam hall.