# 3D Geometry

To pinpoint the precise location of a point in a three-dimensional space, you will need to consider three criteria. Because there are so many questions pertaining to it, three-dimensional geometry plays a significant part in the JEE examinations.

In this article, we will investigate the fundamental ideas of geometry, specifically 3-dimensional coordinate geometry, which will assist in comprehending the various operations that may be performed on a point in a 3-dimensional plane.

The x-axis, the y-axis, and the z-axis are the three axes that make up the three-dimensional Cartesian coordinate system. These axes are mutually perpendicular to one another, and they all use the same units of length. In a manner analogous to the coordinate system used in two dimensions, the point at which these three axes intersect is referred to as the origin O, and the space is segmented into eight octants by means of these axes. The coordinates can be used to represent any point in three-dimensional geometry (x, y, z).

In addition, the coordinates of a point in any of the eight octants are as follows:

(+x,+y,+z), (-x,+y,+z), (+x,+y,-z), (-x,+y,-z), (+x,-y,+z), (-x,-y,+z), (+x,-y,-z), (-x,-y,-z).

## Vectors

In mathematics, a vector is a quantity that possesses magnitude and direction but not position or other characteristics. The quantities of velocity and acceleration are two examples of such quantities.

A thing that possesses both a magnitude and a direction is referred to as a vector. A vector can be conceptualised in terms of geometry as a segment of a directed line, the magnitude of which is equal to the length of the segment, and an arrow is used to indicate the direction of the vector. The direction of the vector is from the end of the vector to the beginning of the vector.

The most fundamental component of any 3D operation is a vector. Quantities in physics that possess both magnitude and distance are referred to as vectors. A vector is a line or other-directed item that connects two or more points in three-dimensional geometry or other areas of mathematics. A position vector is a specialised form of the vector that connects the origin O (0, 0, 0) to the point.

Here, we have the position vector P, which is denoted by an arrow leading from O (which contains the coordinates 0, 0, 0) to P. (1, 1, 1). Take note that the vector’s ending point is defined as the head of the vector, while the vector’s starting point is defined as the tail of the vector.

## Magnitude of a Vector

The length of a vector is quantified by its magnitude, which is expressed as a numerical value. Consider a vector whose head is denoted by the symbol H and whose tail is denoted by the expression T(x1, y1,z1) (x2, y2, z2). If we refer to this vector by its symbol, V, then we may express its magnitude by using the notation |V|, where:

|V| = [{(x2-x1 + (y2-y1 + (z2-z1}] 1/2

## Components of a Vector

Any vector can be defined in terms of its three components if we use a Cartesian coordinate system as our reference point. Any vector can be represented using the following notation:

v = |x| i^ + |y| j^ + |z| k^

Where i, j, and k are the unit vectors that run along the x, y, and z-axes respectively, and where x, y, and z signify the length of the components of the vector that run along these axes accordingly. The magnitude of a vector, denoted by the symbol V, is equal to the sum of the components x, y, and z, and can be written as follows:

|V| = √(|x|²+|y|²+|z|²)

There are three coordinates that are used in the XYZ plane: the x-coordinate, the y-coordinate, and the z-coordinate. Three-dimensional geometry is the application of mathematics to the study of shapes in three-dimensional space. The terms “3D shapes” and “space-occupying shapes” are used interchangeably. 3D shapes can also be characterised as solid shapes that have length, width, and height dimensions. This is another definition of a 3D shape. All known matter may be found inside the confines of a three-dimensional space, which is a geometric model with three parameters. These parameters are denoted by the axes x, y, and z. These three dimensions were selected from the term’s length, width, height, and depth in order to come up with the final answer.

## Conclusion

The mathematical study of three-dimensional shapes in three-dimensional space, known as three-dimensional geometry, requires the use of three coordinates: x-coordinate, y-coordinate, and z-coordinate. To pinpoint the precise location of a point in a three-dimensional space, you will need to consider three criteria. In three-dimensional geometry, the technique of determining the position or location of a point in the coordinate plane is referred to as a coordinate system. One common point is traversed by three lines that are perpendicular to each other. This point is referred to as the origin, and the three lines are referred to as the axes. The x-axis, the y-axis, and the z-axis are their respective names. O is the observer, and his position in relation to that of any other point is what is being measured.

Get answers to the most common queries related to the JEE Examination Preparation.

## Where does the point (0, -2, 5) lies on the plane?

Ans: Given Point is (0, -2, 5). The point has a coordinate of 0 on the X-axis. Therefore, the YZ-pl...Read full

## What exactly are some examples of three-dimensional shapes?

Ans: The term “three-dimensional” or “3D” refers to any and all shapes that...Read full

## Name the first three dimensions.

Ans: These are the dimensions of space, such as x, y, and z; hence, width, length, and height are t...Read full

## What do you mean by a 3D coordinate system?

Ans: The answer is that it is in reference to a Cartesian coordinate system, which is constructed b...Read full

## Is time the fourth dimension?

Ans: The answer is that humans do consider time to be the fourth dimension, but in a very different...Read full