( 1)ln e = 1 .

(2) at e^x = x 。

(3) at e^e = east.

(4)e^(ln x) = x .

(5)de^x/dx = e^x。

(6)d ln x / dx = 1/x .

(7)e^x dx = e^x+c .

(8)∫ xe^xdx = xe^x - e^x + c .

Related content explanation:

E is mathematically a function: lim (1+ 1/x) x, the power of x, and the limit when x approaches infinity.

When people study some practical problems, such as the cooling of objects, the reproduction of cells and the decay of radioactive elements, they must study lim (1+ 1/x) x, the x power of x, and the limit when x approaches infinity. It is this limited isomorphism obtained from infinite changes and developed from two opposite directions that fully embodies the most essential thing of the formation, development and decline of the universe.

Some people say that beauty lies in the rhythm of things, and the "laws of nature" also have this rhythm; Some people say that beauty is a dynamic balance and eternal change, so "natural law" is also a dynamic balance and eternal change; Some people say that beauty lies in the dynamic structure of things, so the "laws of nature" also have this structure-such as hairspring in watches, clockwork in machines and so on.