(sinx)'=cosx

Use dy/dx to represent the higher derivative.

Then dy/dx=cosx, dy=cosx*dx.

Then ∫ is the integral sign, which is equivalent to the inverse operation of the derivative (not exactly)

Expressed as ∫dy

For example, ∫cosx*dx is asking whose derivative is equal to cosx.

According to cha ∫cosx*dx=sinx (endless)

But add a C.

C is an arbitrary constant.

supplement

You don't even know cos sin!

Sine and cosine are symbols of trigonometric functions.

That is, draw a right triangle first.

Among them, the two right-angled sides are a and b respectively, and the hypotenuse is C.

The angles corresponding to the edge are angle a, angle b and angle C.

So Sina = A/C COSA = B/C.

sinB=b/c cosB=a/c

This is called trigonometric function.