Dear aspirant,

In 1st year syllabus of every branch and every student remains same. There is nothing different taught in non core and core branches. Yes maybe 1 or 2 subjects are different but main subjects are same.

Coming to main part of your question,

In maths - You only need to keep in your mind that is diffrential equations, matrices and calculus.

In Physics- Basics taught in 11th and 12th that is electromagnetism and magnetic effects of current.

In chemistry - You don't need anything. You need to just memorize whatever notes you get from college.