Calculus is divided into differential calculus and integral calculus. The basic and core idea of differential calculus and integral calculus is limit, which runs through the whole process, so we must first master the definition of limit.

The central problem of differential calculus is derivative, which is geometrically embodied as tangent problem, and derivative is also the limit of function change rate, so we must master and understand the definition of derivative; The central problem of integral is quadrature, which is the inverse process of derivative and more difficult than differential calculus. Integral can be divided into indefinite integral and definite integral. It is worth noting that the definitions of indefinite integral and definite integral are different, but definite integral can be solved by indefinite integral algorithm.

The difficulty of calculus is the derivative and quadrature of compound function, that is, the application of the idea of substitution, which requires more questions to better understand.

Then we need to find out the test sites of calculus, which will be more targeted, such as equivalent infinitesimal replacement, finding limit, continuity and discontinuity, finding the derivative at the breakpoint of broken function, higher derivative, L'H?pital's law, maximum problem (finding the first derivative), concave-convex problem (finding the second derivative), and finding the integral with method of substitution and integration by parts.

Finally, read the book at least three times, each time I believe there will be new gains, coupled with appropriate exercises, we can certainly learn calculus well.