Who invented infinitely small?

Leibniz (1646-1716) was born in laibniz, Germany. During his youth, Leibniz studied law. In 1672, raprenz traveled to Paris, France, where he came into contact with some geometric works. From then on, raprenz fell into the "Obsession" of mathematics research. In 1675, in order to study the local State (or behavior) of function f (x) near a "point X", 29-Year-Old laveniz invented a "new method". That is to say, leveniz introduces a very small "ideal number" (a "fictional thing" of thinking). This kind of "ideal number" is different from the ordinary real number (that is, it has a different "quality"). However, this kind of "ideal number" has the same operation attribute as the real number, for example, it can participate in various arithmetic operations of real numbers to form a "mixed Number System". It is interesting that this kind of "ideal number" is so special and small that it can be omitted when they are not needed.

Leveniz defines the "derivative" of function f (x) in this way. First, the expression is introduced.

(*) (F (x + dx)-f (x)/dx

In this (*) expression, dx is the "ideal number". After a certain calculation process, the constant transformation of the expression into a definite real number D and a very small, negligible function expression containing dx "and" (SUM ). In this case, leveniz calls the new separated definite real number D as the "Number of Exports" ("derivative") of function f (x) at point X.

Leveniz used this "invention" to combine micro-learning and integral points into a discipline called calculus ). This kind of "ideal number" invented by laveniz is a little weird and has been criticized by future generations. However, whatever it is (criticized by future generations), this kind of "ideal number" in laveniz is still very vital and creative, this "ideal number" has led to the emergence of many important research results, and these research results are correct and can withstand the scientific conclusions of the time postgraduate entrance exam.

Later, people began to call this tiny, sometimes negligible, "ideal number" called "infinitesimal", that is, "infinitely small" (infinitely
Smaall ). In history, calculus was originally called an infinitely small calculus (infinitesimalcalculus ). Three hundred years later, in 1960,. robinson finally dispelled the dark clouds shrouded in the concept of an infinitely small concept with a rigorous mathematical model theory (or implementation, restoring the scientific dignity of an infinitely small "ideal number.

Robinson (A. Robinson) said: the authenticity of the "ideal number" is neither higher nor lower than the irrational number. It is a tool used for mathematical invention. It can be seen that the concept of Infinitely small is of great scientific value in mathematics research and teaching. Now is the time for the concept to return to mathematics education. We should follow the trend and do not go against the current flow. This is the lesson we learned from the history of mathematics. Let's make it clear. What we have to do now is to introduce the infinite scientific concepts to the broad masses of Chinese young students so that they can grow healthily, become the pillar of the country's future.