Video 3.1. Sistemas de ecuaciones lineales, definición y clasificación

Math & Systems con el Profe Gaspar
4 Oct 202308:16

Summary

TLDRThis video introduces the topic of linear systems of equations in algebra, defining what they are and how they differ from non-linear equations due to the absence of squared or higher degree terms. The script explains the concept of a solution to a system, using an example with two equations and two unknowns, and demonstrates how to find a common solution. It also discusses the classification of systems into compatible (with one or multiple solutions) and incompatible (with no solutions), based on the proportionality of coefficients and constants. The video promises to explore methods for solving these systems in future content.

Takeaways

  • 📚 The video introduces the topic of 'Systems of Linear Equations' in algebra.
  • 🔍 A system of linear equations, also known as a linear system, is a set of linear equations over a commutative ring or field.
  • 📈 The term 'linear' is used because the variables in the equations do not have exponents greater than one, indicating a straight line relationship.
  • 🤝 Two equations with two unknowns form a system when the goal is to find a common solution for both equations.
  • 🔑 The solution of a system is a pair of numbers that satisfies both equations simultaneously.
  • 🔄 Systems of linear equations can be classified into compatible or incompatible based on the number of solutions they have.
  • 💡 A compatible system can be either determined (one unique solution) or indeterminate (multiple solutions).
  • 🚫 An incompatible system is one that has no solution at all.
  • 📝 For a system to have a unique solution, the coefficients of the variables in the equations must not be proportional.
  • 🔄 Infinite solutions occur when the coefficients of the variables and the independent terms of one equation are proportional to those of another.
  • ❌ No solution exists when the coefficients of the variables are proportional, but the independent terms are not.
  • 📈 Graphical methods, as well as other methods to be discussed in future videos, can be used to determine if a system is compatible or incompatible and the type of compatible system.

Q & A

  • What is a system of linear equations?

    -A system of linear equations, also known as a linear system, is a set of equations that are linear, meaning the variables do not have exponents greater than one. They are defined over a commutative ring or field.

  • Why are they called 'linear' equations?

    -They are called 'linear' because the variables in the equations do not have exponents higher than one, and there are no squared, cubed, or higher power terms.

  • What is the solution of a system of linear equations?

    -The solution of a system of linear equations is a set of values for the variables that satisfy all the equations in the system simultaneously.

  • What is the relationship between the equations in a system that has a unique solution?

    -In a system with a unique solution, the equations are not proportional to each other, meaning the coefficients of the variables are not the same when compared across the equations.

  • How can you determine if a system of linear equations has multiple solutions?

    -A system has multiple solutions if the coefficients of the variables in the equations are proportional to each other, and the constant terms are also proportional.

  • What is an incompatible system of linear equations?

    -An incompatible system of linear equations is one where the equations do not have any solution because the coefficients of the variables are proportional, but the constant terms are not.

  • What are the different types of systems of linear equations based on the number of solutions they have?

    -Systems of linear equations can be classified as compatible or incompatible. Compatible systems can be determined (one unique solution) or indeterminate (multiple solutions), while incompatible systems have no solutions.

  • What is the graphical method for solving a system of linear equations?

    -The graphical method is a visual approach to determine if a system of linear equations has a solution by plotting the equations on a graph and observing their intersection points.

Outlines

00:00

📚 Introduction to Linear Systems

This paragraph introduces the concept of linear systems in algebra. It defines a linear system as a set of linear equations over a commutative ring or field. The script provides an example of a linear system and explains why it's called 'linear' due to the absence of variables with exponents greater than one. It further clarifies that a system of two equations with two unknowns seeks a common solution that satisfies both equations simultaneously. The solution is a pair of numbers that, when substituted into the equations, yield the results stated. The paragraph also touches on the classification of linear systems into compatible and incompatible systems, with further subdivisions into determined and indeterminate systems.

05:01

🔍 Conditions for Linear System Solutions

This paragraph delves into the conditions that determine the nature of solutions a linear system can have. It explains that for a system to be determined (having a unique solution), the coefficients of the variables in the equations must not be proportional. The script contrasts this with the case where the coefficients are proportional but the independent terms are not, leading to an incompatible system with no solutions. Conversely, when both the coefficients and the independent terms are proportional, the system is compatible and indeterminate, offering multiple solutions. The paragraph concludes by mentioning the graphical method as a visual approach to determine the compatibility of a system, with the promise of exploring other methods in upcoming videos.

Mindmap

Keywords

💡Algebra

Algebra is a branch of mathematics that deals with symbols and the rules for manipulating those symbols. It is the core of the video's theme, as the script discusses systems of linear equations, which are a fundamental concept in algebra. The video aims to explain how to work with these systems, making 'algebra' central to understanding the content.

💡Linear Equations

Linear equations are mathematical equations in which each term is either a constant or the product of a constant and a single variable. In the video, the script introduces the concept of systems of linear equations, which are sets of linear equations that can be solved simultaneously. The script provides examples of such systems, making it a key concept for understanding the video's message.

💡System of Equations

A system of equations refers to a collection of multiple equations that are solved together. The video script defines a system of linear equations and discusses how to find their common solution. This concept is essential for the video's narrative, as it sets the stage for explaining how to solve for the variables that satisfy all equations in the system.

💡Variables

Variables are symbols used to represent unknown quantities in an equation. The script mentions variables such as 'x1', 'x2', and 'x3' in the context of a system of linear equations. Understanding variables is crucial for grasping how to solve systems of equations, as they represent the quantities we aim to determine.

💡Solution

In the context of the video, a solution refers to the values of the variables that satisfy all the equations in a system. The script explains that the solution to a system of equations is a pair of numbers that, when substituted into the equations, make the equations true. This concept is central to the video's theme, as finding the solution is the ultimate goal of working with systems of linear equations.

💡Compatible System

A compatible system is one in which the equations have at least one solution in common. The video script discusses the conditions under which a system of linear equations is compatible, such as when the coefficients of the variables are not proportional. Understanding compatibility is key to determining whether a system has a unique solution, multiple solutions, or no solution at all.

💡Indeterminate System

An indeterminate system is a type of compatible system that has multiple solutions. The script explains that this occurs when the coefficients of the variables in the equations are proportional, but the constants are not. This concept is important for understanding the variety of solutions that can exist within a system of linear equations.

💡Incompatible System

An incompatible system is one that has no solution. The video script describes this as occurring when the coefficients of the variables are proportional, but the constants are not, leading to a contradiction. Recognizing an incompatible system is important for knowing when a set of equations cannot be solved together.

💡Graphical Method

The graphical method is a visual approach to solving systems of linear equations by plotting them on a graph to see if their lines intersect. The script briefly mentions this method as a way to determine if a system is compatible or incompatible. This method provides a visual understanding of the relationships between equations in a system.

💡Proportionality

Proportionality in the context of the video refers to the relationship between the coefficients of variables in different equations. The script explains that if the coefficients are proportional, it can lead to either a compatible system with a unique solution or an indeterminate system with multiple solutions. Understanding proportionality is essential for determining the nature of a system of linear equations.

Highlights

Introduction to the topic of systems of linear equations in algebra.

Definition of a system of linear equations as a set of linear equations over a commutative ring.

Explanation of why systems are called 'linear' due to the absence of variables with exponents greater than one.

Description of a system of equations with two unknowns and the goal of finding a common solution.

Illustration of how to find the solution to a system of equations using an example with x and y variables.

Demonstration of verifying the solution to a system of equations by substituting values into the original equations.

Classification of systems of linear equations based on the number of solutions they can have.

Differentiation between compatible and incompatible systems of equations.

Explanation of a compatible determined system that provides a unique solution.

Discussion on compatible indeterminate systems that have multiple solutions.

Clarification on incompatible systems that have no solutions.

Conditions for a system of equations to have one, none, or infinite solutions based on the proportionality of coefficients.

Example given to show when a system is compatible because the coefficients are not proportional.

Explanation of when a system has infinite solutions due to the proportionality of coefficients and independent terms.

Example illustrating an incompatible system where coefficients are proportional but the independent terms are not.

Introduction to graphical methods as a visual approach to determine the compatibility of a system of equations.

Mention of other methods that can be used to determine if a system is compatible or incompatible and the nature of the solutions.

Anticipation of further exploration of these methods in upcoming videos.

Transcripts

play00:06

Hola a todos Bienvenidos a un nuevo

play00:10

video de álgebra lineal eh en esta

play00:13

ocasión vamos a comenzar un nuevo tema

play00:15

es el tema tres que lleva por nombre

play00:19

sistemas de ecuaciones

play00:21

lineales y para comenzar digamos con

play00:24

este tema pues vamos a definir

play00:26

precisamente Qué es un sistema de

play00:28

ecuaciones lineal

play00:32

Y bueno pues debemos de conocer que en

play00:35

matemáticas y álgebra lineal un sistema

play00:37

de ecuaciones lineales También conocido

play00:39

como sistema lineal de ecuaciones o

play00:41

simplemente sistema lineal es un

play00:44

conjunto de ecuaciones lineales sobre un

play00:46

cuerpo o un anillo conmutativo así

play00:49

tenemos por ejemplo eh este sistema de

play00:52

ecuaciones lineal que es 3 x1 2 x2 + X3

play00:57

es = 1 2 x1 + 2 x2 + 4 X3 = -2 - x1 +

play01:04

1/2 de x2 - X3 es =

play01:07

0 Por qué se llama lineal Bueno pues

play01:11

principalmente porque como ustedes

play01:13

pueden observar ninguna de las variables

play01:15

eh tiene un

play01:17

exponente mayor que un es decir es

play01:21

lineal no lleva exponente cuadrado cubo

play01:25

ni mucho menos por eso se conoce como

play01:27

lineal es un sistema lineal de

play01:30

ecuaciones

play01:33

eh

play01:37

Ahora dos ecuaciones con dos incógnitas

play01:40

forman un sistema cuando lo que

play01:42

pretendemos de ellas es encontrar su

play01:44

solución común Entonces si nosotros

play01:47

tenemos aquí por ejemplo a1x + b1y = c1

play01:52

y a2x + b2y = a C2 necesitamos conocer

play01:56

el valor de X y el valor de y que

play02:00

satisface a este sistema de ecuaciones

play02:02

es decir qué valor para x y Qué valor

play02:05

para y me da el resultado c1 y el

play02:09

resultado

play02:10

C2 la solución de un sistema es un par

play02:13

de números x1 y1 tal es que reemplazados

play02:17

por reemplazando x por x1 eh Y por y1 se

play02:21

satisfacen a la vez ambas ecuaciones así

play02:23

de esta

play02:25

forma para este sistema de ecuaciones

play02:27

dice que 3x - 4

play02:30

= -6 y 2x + 4y = 16 Nos está dando el

play02:34

resultado que es x = 2 y y = 3

play02:38

eh si ustedes observan Cuando yo

play02:41

sustituyo x y y eh en ambas ecuaciones

play02:45

aquí en 3x - 4y sería 3 * 2 - 4 * 3 e y

play02:51

aquí sustituir x sería 2 * 2 + 4 *

play02:55

3 si nosotros hacemos las operaciones 3

play02:58

* 2 son 6

play03:00

- 4 * 3 son 12 en la de abajo sería 2 *

play03:04

2 = 4 4 * 3 = 12 Si operamos las sumas y

play03:08

restas 6 - 12 nos da -6 4 + 12 = 16

play03:14

entonces observamos que nos da una

play03:17

igualdad si aquí los resultados fueran

play03:20

diferentes es decir si aquí meera un

play03:22

número diferente de -6 y aquí un número

play03:25

diferente de 16 significa que alguno de

play03:27

los dos valores está mal la x o la bien

play03:30

eh pero nos tiene que dar una igualdad

play03:33

en ambas ecuaciones Sí y con ello Bueno

play03:36

pues encontramos precisamente los

play03:38

valores de x y y que satisfacen a este

play03:41

sistema de

play03:42

ecuaciones ahora en el caso de los

play03:45

sistemas de ecuaciones lineales tenemos

play03:47

una clasificación

play03:49

eh según el número de soluciones que

play03:52

pueden tener o que pueden presentar de

play03:54

acuerdo con ese caso se pueden presentar

play03:57

los siguientes casos Entonces tenemos

play04:00

dos tipos de sistemas de ecuaciones

play04:02

puede ser un sistema compatible o un

play04:05

sistema

play04:06

incompatible a su vez el sistema

play04:08

compatible puede ser un sistema

play04:10

compatible determinado el cual nos va a

play04:13

dar una única solución puede ser un

play04:16

sistema también compatible indeterminado

play04:18

en el que podemos tener múltiples

play04:21

soluciones o puede ser que existe un

play04:24

sistema incompatible es decir que el

play04:26

sistema no tiene solución también es un

play04:28

tercer caso que podemos

play04:32

tener

play04:36

Entonces qué condiciones deben cumplir

play04:39

las ecuaciones para que el sistema tenga

play04:41

una ninguna o infinitas soluciones bueno

play04:45

para que un sistema de ecuaciones

play04:47

lineal digamos la característica que

play04:49

debe tener que nos que tenga digamos

play04:53

solución que sea un un un sistema de

play04:57

ecuaciones este determinada

play05:00

eh compatible

play05:03

determinado los coeficientes de x y y de

play05:06

las dos ecuaciones no son proporcionales

play05:09

aquí por ejemplo si vemos este bueno 2x

play05:14

y x sí existe una proporcionalidad Este

play05:18

2x es el doble de X pero en el caso de

play05:21

este no -3y + 5y vemos que no son

play05:26

digamos este

play05:28

proporcionales

play05:30

para que esto se de tendría que ser

play05:32

proporcionales ambos Sí en la misma

play05:36

cantidad aquí por ejemplo si si este

play05:39

fuera en lugar de -3 si fuera un 10y

play05:43

Entonces digamos no sería compatible

play05:47

pero como en este caso son números

play05:49

diferentes es un sistema compatible

play05:54

Okay y lo vamos a ver en la solución de

play05:57

ecuaciones más

play05:58

adelante

play06:01

Ahora cuando nos da infinitas soluciones

play06:04

un

play06:05

eh un sistema de ecuaciones bueno cuando

play06:08

los coeficientes de x y y y el término

play06:10

independiente de una ecuación son

play06:13

proporcionales a los de la otra por

play06:16

ejemplo tenemos esta que dice 2x - 3y =

play06:20

1 y 4x - 6y = 2 la ecuación de abajo es

play06:24

el doble de la primera si yo multiplico

play06:26

2 * 2x es 4x y 2 * 3y son -6y y 2 * 1 es

play06:32

= 2 todos los elementos eh si una

play06:36

ecuación es digamos proporcional a otra

play06:41

Entonces estamos hablando de que podemos

play06:44

tener un sistema con infinitas

play06:46

soluciones un sistema compatible

play06:50

indeterminado ahora el siguiente caso

play06:52

Cuando tenemos ninguna solución es

play06:55

cuando los coeficientes de x y y de una

play06:57

ecuación son proporcionales a los de la

play06:59

otra mientras que los términos

play07:01

independientes no lo son aquí por

play07:03

ejemplo podemos observar que la segunda

play07:05

ecuación eh en los coeficientes de X y Y

play07:09

este 4 es el doble del do y este -6 es

play07:11

el doble de -3 Sin embargo vemos que los

play07:14

términos independientes no son

play07:16

proporcionales no es el doble uno del

play07:18

otro entonces eh aquí podemos decir que

play07:22

es un sistema incompatible es un sistema

play07:26

que no nos va a arrojar ninguna solución

play07:28

podemos verlo así simple vista o podemos

play07:31

calcularlo de alguno de los Por alguno

play07:33

de los métodos uno de los métodos que

play07:35

vamos a aprender es el método gráfico Y

play07:38

eso es más más que nada un método visual

play07:41

para poder eh observar si existe o no

play07:44

una solución pero existen otros métodos

play07:47

que nos permiten

play07:49

determinar si un sistema es compatible o

play07:53

incompatible y en el caso de que sea

play07:55

compatible si es un sistema compatible

play07:58

determinado o es sistema compatible

play08:00

indeterminado es decir que tenga varias

play08:02

soluciones Pero eso lo vamos a observar

play08:06

en los próximos videos sí bien Eso es

play08:09

todo por este video nos vemos hasta la

play08:14

próxima

Rate This

5.0 / 5 (0 votes)

Related Tags
Linear AlgebraSystems of EquationsMathematicsAlgebraic SolutionsEducational VideoSolving TechniquesCompatible SystemsIndeterminate SystemsIncompatible SystemsGraphical MethodAlgebra Tutorial