# Name of the approach used in "Calculus for the practical man" and similar online resources using that approach?

I've begun to read Calculus for the Practical Man and the way they approach the derivatives using only algebra and starting from the concept of rates (chapter 1) is surprising for someone like me that has been taught with limits.

I'm trying to find around the internet more examples of people explaining Calculus with this method of Calculus for the Practical Man but I could not find anything.

What's the name of the method/approach used in this book?

• Please give a simple example of the approach you refer to. Jan 13, 2020 at 22:01
• One example would be at the beginning of the book, the author starts explaining rates and differentials and slowing building up the basics for adding, subtracting derivatives where "Calculus Made Easy" starts with the concept of the infinitesimal and in schools nowadays classrooms starts with the concept of limit. I don't know if this approach starting from the concept of rates has a technical term that I can look for more information.
– Jon
Jan 13, 2020 at 22:09
• For the benefit of those of us not privileged to have the book, please give an explicit simple example of the approach you refer to and place it in the body of the question itself. It will help you get good answers. Jan 13, 2020 at 22:14
• Apologies for my lack of clarity. I added a direct link to the book as luckily it's available on archive.org. The approach I'm curious about the first chapter where he "proves" the sum/subtraction of differentials. I hope it helps.
– Jon
Jan 13, 2020 at 22:23
• Again, please give an explicit simple example of the approach you refer to and place it in the body of the question itself. I suggest you do this if you want good answers. Jan 13, 2020 at 22:25