In the concept of numbers learned in domestic middle schools, any number, whether rational or irrational, positive or negative,

Integer, fraction, the result of multiplying a number by itself is always positive.

If a number multiplies itself to get a negative number, it is called an imaginary number.

Imaginary number is a number that we can't touch at ordinary times, and it is also a strange number, but the concept of imaginary number has been introduced into mathematics.

After that, he created many earth-shattering achievements:

1, which provides a new integration method, especially the integration of trigonometric functions;

2. It provides a solution to the complex impedance problem of capacitance and inductance in AC circuit;

3. Solved the atomic structure problems in chemistry: orbital problem and energy layer problem.

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