lim(x->； A) when x tends to a, f(x) is read as the limit of function f(x).
Like all scientific thinking methods, extreme thinking is also the product of abstract thinking in social practice. The idea of limit can be traced back to ancient times. For example, the secant technology in Liu Hui, the motherland, is an original and reliable application of the limit idea of "approaching constantly" based on the research of intuitive graphics; The ancient Greeks' exhaustive method also contained the idea of limit, but because of their "fear of infinity", they obviously avoided artificially "taking the limit" and completed the relevant proof by indirect proof-reduction to absurdity.
/kloc-in the 6th century, Steven, a Dutch mathematician, improved the ancient Greek exhaustive method in the process of investigating the center of gravity of a triangle. With the help of geometric intuition, he boldly used limit thought to think about problems and gave up the proof of reduction law. In this way, he inadvertently "pointed out the direction of the development of the limit method into a practical concept."
The basic methods for finding the limit are:
1. When the numerator and denominator in the fraction are divided by the highest degree, infinity is calculated as infinitesimal, and infinitesimal is directly substituted into 0.
2. Minus infinite roots, molecules are physical and chemical.
3. Apply the Lobida rule, but the application condition of the Lobida rule is that it is transformed from infinity to infinity or infinitesimal to infinitesimal, and the numerator denominator must also be a continuous derivative function.