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## Introduction to Locus

A locus is a group of points in mathematics that meet a given criterion or geometric attribute. It reflects the path taken by these points as they travel in accordance with the limitations. In coordinate geometry, equations define the connection between the coordinates (x, y) of points producing geometric forms such as circles, parabolas, ellipses, and hyperbolas. Analysing and comprehending loci is essential for problem solving, geometric reasoning, and preparation for advanced mathematical concepts.

### Meaning of locus

In mathematics, a “locus” is the set of all points that meet a specified condition or a specific geometric attribute. It reflects the path taken by these points as they travel in accordance with particular rules or limitations described by a mathematical relationship. Locus notions are frequently found in coordinate geometry, where equations define the connection between the coordinates (x, y) of points producing geometric forms such as circles, parabolas, **ellipses**, and hyperbolas. Understanding and analysing loci is essential in problem solving, geometric reasoning, and many fields of mathematics..

### What is locus

The set of all points that meet a given condition or geometric attribute is referred to as the locus in mathematics. It depicts the path that these points take as they travel in accordance with specific rules or limits established by a mathematical relationship. In coordinate geometry, the phrase is widely used to describe curves, forms, or equations of points having similar properties. Understanding the locus of points is critical for problem solving and geometric reasoning in many areas of mathematics, including algebra, calculus, and complex analysis.

### Locus of points

The collection of all points in a plane that meet a given condition or geometric attribute is referred to as the locus of points. In other words, it reflects the path that these points take as they travel in accordance with particular rules or limitations described by a mathematical relationship. The locus of points is a term used in coordinate geometry to explain curves, forms, and equations of points that have similar properties, such as circles, parabolas, ellipses, and hyperbolas. Understanding the locus of points is essential in many mathematical domains for problem solving and geometric reasoning.

### Locus Theorems

Locus theorems are mathematical principles that describe the locus (set of points) formed by specific geometric conditions. These theorems are used in coordinate geometry to deduce the equations of various curves and shapes.

**Circle Locus Theorem:**The locus of points equidistant from a fixed point (center) is a circle. The distance between any point on the circle and the center is constant, called the radius.**Parabola Locus Theorem:**The locus of points equidistant from a fixed point (focus) and a fixed line (directrix) is a parabola. The distance from any point on the parabola to the focus is equal to its distance to the directrix.**Ellipse Locus Theorem:**The locus of points such that the sum of the distances from two fixed points (foci) is constant is an ellipse. The distance between the foci is the major axis, and the distance from the center to any point on the ellipse is the semi-major axis.**Hyperbola Locus Theorem:**The locus of points such that the absolute value of the difference between the distances from two fixed points (foci) is constant is a hyperbola. The distance between the foci is the transverse axis.**Perpendicular Bisector:**The locus of points equidistant from two fixed points (endpoints of a line segment) is the perpendicular bisector of that line segment.**Angle Bisector:**The locus of points equidistant from two fixed rays (forming an angle) is the angle bisector of that angle.

### Problems on Locus

**Example 1: Circle**

Find the locus of points that are 4 units away from the point (2, 3).

Solution:

The distance between any point (x, y) on the locus and the point (2, 3) is given by:√((x – 2)^2 + (y – 3)^2) = 4

Squaring both sides to eliminate the square root:

(x – 2)^2 + (y – 3)^2 = 4^2

(x – 2)^2 + (y – 3)^2 = 16

The equation (x – 2)^2 + (y – 3)^2 = 16 represents the locus of points that are 4 units away from the point (2, 3), which is a circle with center (2, 3) and radius 4.

**Example 2: Parabola**

Find the locus of points equidistant from the point (0, 2) and the line y = -2.

Solution:

The distance between any point (x, y) on the locus and the point (0, 2) is equal to its distance to the line y = -2.

Distance to the point (0, 2):

√((x – 0)^2 + (y – 2)^2) = √(x^2 + (y – 2)^2)

Distance to the line y = -2:

|y – (-2)| = |y + 2|

Equating the two distances:

√(x^2 + (y – 2)^2) = |y + 2|

Squaring both sides to eliminate the square root:

x^2 + (y – 2)^2 = (y + 2)^2

Simplifying further:

x^2 + y^2 – 4y + 4 = y^2 + 4y + 4

The equation x^2 – 8y = 0 represents the locus of points equidistant from the point (0, 2) and the line y = -2, which is a parabola opening upward with its vertex at the origin (0, 0).

## Frequently asked questions about Locus

### What is meant by Locus?

The set of points that meet a given criterion or geometric attribute is referred to as a locus. It illustrates the path taken by a point or points as they travel in accordance with the limitations. In mathematics, locus is used to define curves, forms, and equations of points with similar properties.

### What is meant by the locus of points

The locus of points is the collection of all points on a plane that meet a specific condition or criterion. It denotes the route or form traced by these points as they travel in accordance with the rules or limits given by a mathematical relationship or geometric feature.

### What is the locus of a straight line?

A straight line's locus is the set of all points on the line. It generates a one-dimensional figure with infinite points that meet the equation or condition that defines the location and orientation of the line in a two-dimensional plane.

### What is the equation of locus

A locus equation is a mathematical formula that specifies the connection between the coordinates (x, y) of points that constitute a certain geometric shape or curve. It specifies the conditions or limitations under which the points on the locus are located. Depending on the nature of the locus, the equation can take several forms, such as algebraic, trigonometric, or parametric.

### How to find the locus in mathematics

To find the locus in mathematics, follow these step-by-step instructions: Define the Condition: Identify the condition or geometric property that the points on the locus must satisfy. Express the Condition Algebraically: Translate the geometric condition into an algebraic equation involving the coordinates (x, y) of the points on the locus. Simplify the Equation: Manipulate the equation to simplify it by expanding, factoring, or rearranging terms.

### What is an example for locus?

The locus of points equidistant from two fixed locations is an example of a locus. The perpendicular bisector of the line segment connecting the two fixed points is known as this locus. Any point on this locus will be the same distance from both fixed points, resulting in a straight line that bisects the line segment.

### What is the definition of parabola in terms of locus

A parabola is described in terms of locus as the locus of points that are equidistant between a fixed point (focus) and a fixed line (directrix). A parabola is the set of all points in a plane such that the distance between each point and the focus equals the perpendicular distance between that point and the directrix. This attribute distinguishes a parabola's form, which can expand upward or downward depending on the orientation of the focus and directrix.

### What is the definition of ellipse in terms of locus?

An ellipse is defined as the locus of points on a plane where the sum of the distances between each point and two fixed points (foci) is constant. An ellipse is the set of all locations where the sum of the distances between any two points on the ellipse remains constant. This one-of-a-kind attribute produces the distinctive shape of an ellipse, which resembles a flattened circle with two foci situated within the ellipse. The length of the major and minor axes dictates the ellipse's size and direction.

### What is the definition of Hyperbola in terms of locus?

Introduction: A hyperbola is defined as the locus of points on a plane where the absolute value of the difference in distances between each point and two fixed points (foci) is constant. A hyperbola is the set of all points on a hyperbola where the absolute difference in distances from any point on the hyperbola to the two foci stays constant. This one-of-a-kind quality gives rise to the hyperbola's distinctive form, which consists of two different curves that extend outward from each other and have asymptotes. The size and form of the hyperbola are determined by the distance between the foci.

### What is the locus in class 12

The notion of locus is often taught in the context of coordinate geometry in Class 12. The set of points that meet a given criterion or geometric attribute is referred to as a locus. Students learn how to solve loci equations, which are algebraic expressions that indicate the connection between the coordinates (x, y) of the points on the locus.