1, and establish an appropriate rectangular coordinate system;

2. Let the plane normal vector n=(x, y, z);

3. Find two vectors that are not * * * straight lines in the plane, and record them as a=(a 1, a2, a3) b=(b 1, b2, b3);

4. According to the definition of normal vector, the equation 1NA = 02NB = 0 is established;

5. Solve the equation and take one of the solutions.

Regarding the calculation method of normal vector differential geometry, it involves the representation of surfaces. Usually the surface is expressed as:

(1) implicit function: F(x, y, z)=0, such as plane x+y x+y+z = 0；;

(2) (parameterized) vector form: r (u, v) = x (u, v) I+y (u, v) j+z (u, v) k. Because the dimension of a surface is 2, there are generally two parameters u, v ... For example, x+y+z=0 can be expressed as: r.

Accordingly, the method of calculating the vector is as follows:

( 1)grad(F)。 That is, the gradient grad(F) of the implicit function f (x, y, z) is the normal vector of the surface at (x, y, z), that is, the normal vector is the direction with the largest change rate of F(x, y, z) = c.