1, a very large number, can be expressed by e number, such as 623000000000, and can be expressed by 23E 12.
2. The number e indicates that the number form 23 * 10 12e is 23E 12, that is to say, the decimal point next to the number 6 in the number 23 is shifted to the right by 12.
3.e number is a quantitative control in scientific counting, which can count and represent data, making counting more regular and representative, that is, 7 * 10 4 = 7E4.
But when it comes to e, there is a formula that has to be mentioned, and that is Euler's identity-known as the most beautiful formula in the world.
The five most basic constants in mathematics-0, 1, pi, the base E of natural logarithm and imaginary unit I, and the two most basic symbols in mathematics, equal sign and plus sign, are connected by a simple identity, which is really amazing.
This equation has a geometrically intuitive explanation. Real number can be represented by a vector on the real number axis, and rotating this vector is equivalent to multiplying an imaginary number I. Based on this, a coordinate system with real number as the horizontal axis and imaginary number as the vertical axis is established.
If the real unit vector rotates π/2 counterclockwise every time, the results of 1, I,-1, -i, 1 can be obtained respectively, that is, it returns to its original position after four rotations. However, when the real unit vector keeps the same length and rotates θ, the vector obtained is: cosθ+isθ. According to Euler formula e? Iθ= cosθ+isθ。 It can be seen that eiθ represents the real unit vector 1 after rotating θ. So eiπ means that the unit vector rotates π counterclockwise, and the result is obviously-1.