In mathematics, a vector is a set of numbers arranged in a specific order, and can also be elements of other types, such as complex numbers or matrices. Vectors are usually represented by bold lowercase letters, such as v \mathbf{v}v , where each value or element is called a component of the vector. Vectors can represent the direction and size in space, and can also be used to represent the motion or change of objects. The length of a vector is called the modulus length, which can be obtained by calculating the sum of the squares of each component and taking the square root. Vector addition and multiplication are two basic operations of vectors, and they follow specific rules and algorithms. Vectors are used in many subdisciplines such as physics, computer science, engineering, and statistics.
direction angle direction cosine
projection
quantity product
vector product☆
Linear algebra third-order determinant knowledge in advance:
Definition of second order determinant
If reverse sequence number = even number, it is called even arrangement
If reverse sequence number = odd number, it is called odd arrangement
End of Supplementary Knowledge of Linear Algebra
Planes and Equations
The method of determining a line by two points:
Example 2 The second method:
Answer 2 using Cramer's Law :
