Hey Aspirant, Admission in IISER(Indian Institute of Science Education and research ) is given via 3 channels you must meet the requirement of at least one of them in order to get the admission.

The three channels are:

• Jee channel: admission is given on the basis of rank secured in Jee mains
• KVPY channel: admission is given on the basis of KVPY fellowship and cutoff of marks in KVPY
• SCB channel: Candidates have to appear for IISER aptitude test for admission.

This Aptitude test is of 3 hours and consists of Multiple choice questions from four subjects of equal weightage namely Maths, Chemistry, Physics and Biology of total 180 marks.

You will have to study maths on your own or separately if you want to get a good score.

Do check more about the test and syllabus on the link below:

https://engineering.careers360.com/articles/iiser-admission

All the best.