Question regarding baby do Carmo's definition of a regular surface.

differential-geometry multivariable-calculus derivatives definition

Solution 1:

DoCarmo is taking the word differentiable to mean smooth or $C^\infty$.

Related

List data structures in JavaScript
Is there a reason not to use SparkContext.getOrCreate when writing a spark job?
The collection nested inside firebase collection's model doesn't have add function
Why my JavaFX TableView is empty
Code breaks when updating jQuery due to changes in toggle
Google Apps Script HTML Form
Representing Points on a Circular Radar Math approach
Mocking dayjs extend
iOS Swift Multiple dimension arrays - compiliing takes ages. What should I change?
Using getchar() in a while loop
Sobel derivative in OpenCV
memory issues when transforming np.array using to_categorical