Hello aspirant,

Since you're from CHSE Odisha and you're failing to understand the theory of elements, don't need to be worried. As you know, the CBSE, ICSE and CHSE has almost the same syllabus so that the students can prepare for their respective boards as well as for preparing difference common entrance tests. Anyways, you can use the Arihant complete course for Mathematics as a reference book, not as textbook. See, this is because you can take a help from the book, but if you don't follow your own textbook, then problem may arise in your board exam. So ty to study along with your prescribed board textbook and see if there're any similarities between your Maths textbook and the Arihant one. If you find, then it'll be easy for you to study and if not, you can refer to Arihant book for better understanding and try to solve the questions of your prescribed textbook. You will understand slowly but clearly too. Besides, you can use RD Sharma maths textbook for CBSE. It will clear your fundamentals and solve all your doubts at ease.

Hope, it helps you.