Definition of Position Vector
A position vector is a vector that starts from point O (origin) in a coordinate system and ends at another point. This vector plays an important role in determining the position or location of a point in a coordinate system.
Characteristics of Position Vectors
Each position vector has the following characteristics:
- Always starts from the origin O (center of coordinates)
- Ends at a specific point in the coordinate system
- The coordinates of the position vector are the same as the coordinates of its endpoint
Representation of Position Vectors
In general, if we have a point P with coordinates in a plane, then the position vector from point O to point P can be written as .
In three-dimensional space, if point P has coordinates , then its position vector is .
In the visualization below, we use the notation OA, OB, OC, and OD to indicate position vectors from point O to specific points (A, B, C, or D).
Examples of Position Vectors
Suppose there are two points A and B in the coordinate plane:
- Point A with coordinates
- Point B with coordinates
Then the position vectors of these two points are:
Benefits of Position Vectors
Position vectors have several benefits in mathematics and its applications:
- Determining the location of a point in a coordinate system
- Serving as a basis for calculating other vectors such as displacement vectors
- Facilitating the solution of problems related to position and location
- Used in GPS technology to determine the position of a location
Relationship with Displacement Vectors
Displacement vectors can be obtained from the difference between two position vectors. If we have position vectors and , then the displacement vector from A to B is:
From the previous example, the displacement vector from A to B is:
Therefore, to move from point A to point B, we need to move 10 units to the right and 3 units upward.