In my previous post I mentioned about learning calculus from Tom Apostol calculus and it is a rigorous introduction to the subject. It is my first encounter with proof based mathematics , in fact I didn't even knew that you need to learn something called "Proof writing" before touching a rigorous text ( many people recommend this) . I just searched about a good calculus book on the net and Tom Apostol's book was there , I read the introduction of this book and it was very interesting so I continued . I didn't knew about Proof writing because I was never educated about it and there are gaps in my learning because of bad schooling ( I am still in high school ) and no mentorship or guidance therefore i am largely self taught. I also didn't liked the teaching in school and was more interested to find answers to my own questions.

Some people suggested me that i should first learn to read and write proofs before reading a rigorous text and suggested books like "How to prove it" by Daniel J velleman.…