This book had a really gentle explanation of the required calculus: https://www.amazon.com/Make-Your-Own-Neural-Network-ebook/dp/B01EER4Z4G https://www.amazon.c

This book had a really gentle explanation of the required calculus: https://www.amazon.com/Make-Your-Own-Neural-Network-ebook/dp/B01EER4Z4G https://www.amazon.com/Make-Your-Own-Neural-Network-ebook/dp... It also builds some really simple Python code to create a simple (non-"deep", i.e. with just one hidden layer) neural network capable of recognizing human-drawn digits with good accuracy.