Fundemental Theoreom of Calculus version 1

I managed a very 'weak' proof of FTC1, still it was fun and will come in handy when I see better proofs and how they solved the parts that I treated with too little formality.

I also included in a second part, yet another intuitive perspective on the theorem, using simple infinitesimal algebra.

http://jadnohra.net/release/math/ftc1.pdf

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