FUNCTIONS | SHS GRADE 11 GENERAL MATHEMATICS QUARTER 1 MODULE 1 LESSON 1

00:23:14
https://www.youtube.com/watch?v=8t875zSYkOc

概要

TLDRCette vidéo présente une leçon de mathématiques générales pour les élèves de 11e année, axée sur les fonctions de la vie réelle. Les objectifs incluent la détermination des fonctions et des relations, l'illustration des fonctions à l'aide de diagrammes de correspondance, d'ensembles et de graphiques, ainsi que la représentation de situations réelles à l'aide de fonctions. Les concepts clés abordés comprennent le domaine, la portée, les relations, les fonctions, et les tests de ligne verticale pour identifier les fonctions. Des exemples de fonctions dans la vie quotidienne, comme la longueur de l'ombre d'une personne ou la position d'une voiture dans le temps, sont également fournis. La leçon se termine par un exercice d'évaluation pour tester la compréhension des élèves.

収穫

  • 📝 Préparez du papier et un stylo pour les exercices.
  • 📊 Les fonctions relient des valeurs d'entrée à des valeurs de sortie.
  • 🔍 Utilisez le test de la ligne verticale pour identifier les fonctions dans les graphiques.
  • 📈 Les diagrammes de correspondance montrent comment les éléments sont associés.
  • 📚 Le domaine est l'ensemble des valeurs d'entrée d'une fonction.
  • 📏 La portée est l'ensemble des valeurs de sortie d'une fonction.
  • 🔗 Une fonction associe chaque x à un seul y.
  • 🧩 Les ensembles sont des collections d'objets distincts.
  • 🚗 La position d'une voiture est une fonction du temps.
  • 🌞 La longueur de l'ombre est une fonction de la hauteur.

タイムライン

  • 00:00:00 - 00:05:00

    Cette vidéo est une introduction aux fonctions et relations en mathématiques générales pour les élèves de 11e année. Les objectifs incluent la détermination des fonctions, l'illustration des fonctions à travers des diagrammes de correspondance, des ensembles et des graphiques, ainsi que la représentation de situations réelles à l'aide de fonctions. Un puzzle de mots croisés est utilisé pour rappeler des termes mathématiques importants, tels que relation, paire ordonnée, domaine, ensemble et plage.

  • 00:05:00 - 00:10:00

    Une fonction est définie comme une relation spéciale où chaque valeur x est associée à une seule valeur y. Des illustrations, comme des diagrammes de correspondance, aident à comprendre cette notion. Les exemples montrent comment vérifier si une relation est une fonction en s'assurant que chaque élément du domaine est associé à une seule valeur dans la plage. Les élèves sont encouragés à identifier des fonctions à partir d'exemples donnés.

  • 00:10:00 - 00:15:00

    Les élèves apprennent à utiliser des ensembles pour déterminer si une relation est une fonction. Si aucune valeur x n'est répétée dans un ensemble d'ordonnées, alors c'est une fonction. Des exemples supplémentaires sont fournis pour illustrer cette méthode. Les élèves sont également introduits au test de la ligne verticale (VLT) pour déterminer si un graphique représente une fonction, en vérifiant si une ligne verticale touche le graphique à un seul point.

  • 00:15:00 - 00:23:14

    Enfin, des exemples de fonctions dans la vie réelle sont présentés, comme la circonférence d'un cercle en fonction de son diamètre, la longueur de l'ombre d'une personne en fonction de sa hauteur, et la position d'une voiture en fonction du temps. Un exercice d'évaluation de 10 questions est proposé pour tester la compréhension des élèves, suivi d'un rappel des concepts clés abordés dans la leçon.

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ビデオQ&A

  • Qu'est-ce qu'une fonction ?

    Une fonction est un type spécial de relation où chaque valeur d'entrée (x) est associée à une seule valeur de sortie (y).

  • Comment identifier une fonction à partir d'un graphique ?

    On utilise le test de la ligne verticale (VLT) : si une ligne verticale touche le graphique en plus d'un point, ce n'est pas une fonction.

  • Qu'est-ce que le domaine d'une fonction ?

    Le domaine est l'ensemble de toutes les valeurs d'entrée (x) d'une fonction.

  • Qu'est-ce que la portée d'une fonction ?

    La portée est l'ensemble de toutes les valeurs de sortie (y) d'une fonction.

  • Comment illustrer une fonction ?

    Les fonctions peuvent être illustrées à l'aide de diagrammes de correspondance, d'ensembles ou de graphiques.

  • Donnez un exemple de fonction dans la vie réelle.

    La longueur de l'ombre d'une personne est une fonction de sa hauteur.

  • Qu'est-ce qu'un ensemble en mathématiques ?

    Un ensemble est une collection d'objets bien définis et distincts, appelés éléments.

  • Quelle est la différence entre une relation et une fonction ?

    Une relation peut associer une valeur d'entrée à plusieurs valeurs de sortie, tandis qu'une fonction associe chaque valeur d'entrée à une seule valeur de sortie.

  • Comment vérifier si un ensemble est une fonction ?

    Un ensemble est une fonction si aucun x n'est répété dans les paires ordonnées.

  • Qu'est-ce qu'un couple ordonné ?

    Un couple ordonné est une paire d'objets pris dans un ordre spécifique, généralement noté (x, y).

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  • 00:00:01
    hello there and welcome to
  • 00:00:03
    our new lesson this video is for senior
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    high school
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    general mathematics for grade 11.
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    prepare the following a paper and a pen
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    for you to write your answers or
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    solutions
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    for the problems later on and remember
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    you can always pause and play this video
  • 00:00:28
    whenever necessary you can even go back
  • 00:00:32
    or revisit the portion of this video to
  • 00:00:34
    clarify some things
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    for mastery purposes i hope that you are
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    all excited for this so let's hop in
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    this video presentation is for the first
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    quarter
  • 00:00:47
    module 1 of our subject general
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    mathematics
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    for grade 11. the topic is
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    real life functions to be specific
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    this is for the first lesson about real
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    life functions
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    what you need to know we have three main
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    objectives for this
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    session the first one is we are going to
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    determine functions and relations
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    second illustrate functions through
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    mapping diagrams
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    sets and graphs and finally you're going
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    to represent
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    real life situations using functions
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    what's in what you see on the screen
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    right now
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    is a crossword puzzle exactly
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    we have here five descriptions of
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    different terms
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    that is related to your junior high
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    school mathematics
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    these are necessary terms for us to
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    proceed with our new lesson
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    okay so you can pause this video
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    and try to recall those important terms
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    i'll give you time go ahead pause the
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    video
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    are you done that sounds great so let's
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    reveal the answers so for number one
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    let's have number one down
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    a rule that relates values from a set of
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    values which we call as domain
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    to a second set of values which we call
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    as range
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    what do you think the answer is
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    relation so let's put it in our
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    crossword puzzle
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    relation there
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    number three three down blank
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    pair pair of objects taken
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    in a specific order what do you call
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    this
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    blank pair the answer is it's an
  • 00:02:43
    ordered pair very good so let's put it
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    in our crossword puzzle now to clarify
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    about
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    ordered pairs we have here an example
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    remember that ordered pairs are a
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    sequence of two elements
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    like for this example one and two they
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    are enclosed in a parenthesis and they
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    are separated by a comma
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    okay that's an ordered pair let's
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    proceed to the next one
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    how about across number two the set of
  • 00:03:15
    all x or input values can you recall
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    you have there your clues o and i for
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    the second and the second to the last
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    letter
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    and the answer is domain right
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    brilliant domain let's review about
  • 00:03:31
    domain
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    when we say domain look at the example
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    we have four sets
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    or we have four ordered pairs in this
  • 00:03:39
    set
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    one seven two six three five
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    and four four now what is our domain
  • 00:03:47
    here
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    our domain are the first elements inside
  • 00:03:51
    the parenthesis or first element in each
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    of the ordered pairs
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    so that means it's 1 2 3
  • 00:03:59
    and four which serves as our domain
  • 00:04:05
    how about for number four across
  • 00:04:08
    collection of well-defined
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    and distinct objects called elements
  • 00:04:13
    that share a common characteristic
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    you have this when you're still in grade
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    seven the answer is
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    well done that's set s84
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    set last one
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    across number five the set of all y
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    or output values what do you call that
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    your clue there is it ends with letter e
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    you already have the domain this is the
  • 00:04:42
    pair of domain
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    that means we are referring to the range
  • 00:04:46
    okay we have completed our crossword
  • 00:04:48
    puzzle but before that let's clarify on
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    range
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    now using the same example for the
  • 00:04:53
    domain
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    we have here this set of ordered pairs
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    we already have one two three four as
  • 00:04:59
    our domain earlier right
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    now this time the range is these values
  • 00:05:05
    the second element of each ordered pair
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    or the y values that will be 7
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    6 5 and 4 in this example
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    what's new what makes relation
  • 00:05:21
    a function
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    a function is a special kind of relation
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    because it follows an extra rule
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    just like a relation a function is also
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    a set of ordered pairs however
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    take note of this every x
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    value must be associated to
  • 00:05:45
    only one y value i repeat
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    every x value must be associated
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    to only one y value that's the most
  • 00:05:57
    important part of this lesson
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    remember that that's for the definition
  • 00:06:02
    of our function
  • 00:06:04
    illustrations will help us a lot to
  • 00:06:07
    learn
  • 00:06:08
    functions easily so we have here mapping
  • 00:06:11
    sets and graphing a function is a
  • 00:06:14
    special type of relation
  • 00:06:16
    always remember that in which each
  • 00:06:19
    element
  • 00:06:20
    of the domain is paired with exactly
  • 00:06:23
    one element in the range a mapping
  • 00:06:26
    shows how the elements are paired
  • 00:06:30
    it's like a flowchart for a function
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    showing the input and the output of
  • 00:06:35
    values
  • 00:06:36
    like this the domain for the first set
  • 00:06:40
    and the range for the second set now in
  • 00:06:43
    this
  • 00:06:43
    mapping let's identify if this is
  • 00:06:46
    a function or not a function how do we
  • 00:06:50
    do that
  • 00:06:51
    recall every x
  • 00:06:54
    value must be associated to
  • 00:06:57
    only one y value so basing on that
  • 00:07:02
    let's try to check if every element in
  • 00:07:04
    our domain
  • 00:07:06
    is associated to only one value in our
  • 00:07:09
    range
  • 00:07:10
    let's focus on this part our domain a
  • 00:07:13
    is associated to roman numeral one
  • 00:07:17
    so that's one is to one that's the
  • 00:07:19
    correspondence
  • 00:07:20
    second domain or second element b
  • 00:07:23
    that is associated to only one
  • 00:07:26
    y value that is roman numeral 2.
  • 00:07:30
    here c third element
  • 00:07:33
    of our domain is associated to
  • 00:07:36
    or is being paired to only one value of
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    y
  • 00:07:40
    that is 3 or roman numeral 3. and lastly
  • 00:07:44
    d in our domain is being paired
  • 00:07:47
    with roman numeral 4 in our range
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    so as you can see every element in our
  • 00:07:54
    domain
  • 00:07:56
    is being paired to only one value
  • 00:07:59
    of y in our range so that
  • 00:08:02
    means this example is
  • 00:08:07
    correct this is a function
  • 00:08:11
    let's look at example number two can you
  • 00:08:14
    identify
  • 00:08:14
    if the given is a function or not a
  • 00:08:17
    function
  • 00:08:18
    you may pause this video
  • 00:08:21
    okay all right so how about this example
  • 00:08:26
    this is still a function y
  • 00:08:30
    looking at all the elements of our
  • 00:08:33
    domain negative 3 is being paired to 0
  • 00:08:36
    negative 1 is being paired to 4 2
  • 00:08:39
    is being paired to 7 and 4 is being
  • 00:08:43
    paired to 4.
  • 00:08:44
    so this shows that every element in our
  • 00:08:47
    domain
  • 00:08:47
    is being mapped or is being paired to
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    only one
  • 00:08:51
    value in our range which means
  • 00:08:55
    that if we have an input of negative
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    three the output is only zero
  • 00:08:59
    if we have an input of negative one the
  • 00:09:02
    output is
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    only four we don't have any other y
  • 00:09:06
    values
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    if we have an input of two therefore our
  • 00:09:09
    output is seven
  • 00:09:11
    if our input is four our output is also
  • 00:09:15
    four this type of correspondence shows
  • 00:09:18
    many is the one for this part we have
  • 00:09:20
    two elements in our domain
  • 00:09:23
    here that's negative one and four we
  • 00:09:26
    have two elements in our domain
  • 00:09:28
    that has the same value in our range
  • 00:09:30
    take note
  • 00:09:31
    what we are referring to in a function
  • 00:09:33
    is we have
  • 00:09:35
    every element in our domain is paired
  • 00:09:38
    with
  • 00:09:38
    one element in our range which means
  • 00:09:41
    that for every input there's only one
  • 00:09:44
    output this type of correspondence is
  • 00:09:46
    considered
  • 00:09:47
    as a function i hope that's clear so
  • 00:09:50
    this is
  • 00:09:51
    a function third example how about this
  • 00:09:54
    is this a function or not a function you
  • 00:09:56
    may pause this video
  • 00:09:59
    and let's reveal this is not a function
  • 00:10:04
    why earlier we saw
  • 00:10:07
    many is the one correspondence right
  • 00:10:10
    this time
  • 00:10:11
    you call this type of correspondence
  • 00:10:13
    recall your grade seven
  • 00:10:14
    and grade eight mathematics in your
  • 00:10:17
    junior high school
  • 00:10:18
    this is for this element in our domain
  • 00:10:22
    which is letter a
  • 00:10:23
    it's being paired let's focus on that
  • 00:10:25
    here
  • 00:10:26
    that's our domain a it's being paired to
  • 00:10:30
    one roman numeral 1 in the range at the
  • 00:10:33
    same time
  • 00:10:34
    the same element in the domain is being
  • 00:10:36
    paired to
  • 00:10:38
    roman numeral 3. now that means
  • 00:10:42
    this element in the domain has two
  • 00:10:44
    outputs
  • 00:10:45
    one and three which is clearly a
  • 00:10:48
    violation of the definition of our
  • 00:10:50
    function right
  • 00:10:52
    therefore basing on that element
  • 00:10:55
    this example is
  • 00:10:58
    not a function i hope i made that clear
  • 00:11:02
    a is being paired to two values in our
  • 00:11:04
    range
  • 00:11:06
    we are done with the mapping again these
  • 00:11:08
    are illustrations to help us out
  • 00:11:10
    understand or identify if the given is a
  • 00:11:14
    function
  • 00:11:14
    so this time let's move on to sets sets
  • 00:11:18
    in this example we will have rooster
  • 00:11:20
    notation
  • 00:11:21
    so we have a set of four ordered pairs
  • 00:11:24
    beginning with two three
  • 00:11:28
    four five five six
  • 00:11:31
    and we have six seven now can you
  • 00:11:34
    identify if this given set
  • 00:11:36
    is a function or not a function
  • 00:11:40
    now how do we do that let's identify
  • 00:11:42
    first the x
  • 00:11:43
    and the y elements in each ordered pair
  • 00:11:46
    so for the first one here
  • 00:11:48
    two is our x sub one three
  • 00:11:51
    is our y sub one four is our second
  • 00:11:55
    value of x in the second ordered pair
  • 00:11:58
    five is our y sub two five
  • 00:12:01
    is our x sub three in the third ordered
  • 00:12:03
    pair
  • 00:12:04
    six is our y sub three here
  • 00:12:07
    in the fourth ordered pair this will
  • 00:12:09
    serve as our
  • 00:12:11
    x of four and this will be our y sub
  • 00:12:13
    four which is seven
  • 00:12:15
    now why is it important for us to
  • 00:12:18
    identify
  • 00:12:19
    our x and y's in each of the ordered
  • 00:12:22
    pairs
  • 00:12:23
    because these values in a domain
  • 00:12:28
    are the critical values so identify if
  • 00:12:31
    it's a function or not a function
  • 00:12:33
    why look at this we have 2 4 5
  • 00:12:36
    and 6 in the domain no x value
  • 00:12:40
    is repeated so 2 is distinct from the
  • 00:12:44
    rest of the domain that's
  • 00:12:45
    4 5 and 6. thus we consider
  • 00:12:48
    this as a function
  • 00:12:52
    this set is a function remember that
  • 00:12:56
    when there's no x value that has been
  • 00:12:58
    repeated in the given set
  • 00:13:00
    then that means it's a function second
  • 00:13:03
    example
  • 00:13:04
    this set we have three three four five
  • 00:13:07
    five five and five four so again
  • 00:13:11
    the first step is let's identify the x
  • 00:13:14
    and the y
  • 00:13:14
    elements like this followed by
  • 00:13:19
    yes we are going to identify the domain
  • 00:13:22
    so meaning all the x values in our
  • 00:13:24
    ordered pairs
  • 00:13:25
    we have 3 4 5 and 5.
  • 00:13:29
    now notice that here 5
  • 00:13:32
    is repeated that's the x value it's
  • 00:13:35
    repeated for that element in our x or in
  • 00:13:39
    our domain
  • 00:13:40
    we do have two different outputs which
  • 00:13:43
    is not
  • 00:13:43
    anymore the definition of a function so
  • 00:13:46
    this is
  • 00:13:47
    not a function well done
  • 00:13:51
    we are done with the second illustration
  • 00:13:53
    for sets
  • 00:13:54
    again we are done with mapping and we
  • 00:13:56
    are done with sets now this time let's
  • 00:13:58
    focus
  • 00:13:59
    into another way that's for graphing
  • 00:14:03
    how do we identify if the given graph is
  • 00:14:06
    a function or not
  • 00:14:07
    your clue there is being pointed it's
  • 00:14:10
    vlt
  • 00:14:11
    that would be our magic keyword to
  • 00:14:13
    identify if the graph
  • 00:14:14
    is a function or not how what do you
  • 00:14:17
    mean by
  • 00:14:18
    vlt vlt stands for
  • 00:14:22
    vertical line test
  • 00:14:26
    yes functions can also be determined in
  • 00:14:29
    graphing we can use this vertical line
  • 00:14:32
    test which is a special kind of test
  • 00:14:35
    using imaginary vertical lines
  • 00:14:38
    and to check if these vertical lines
  • 00:14:41
    would touch the graph only
  • 00:14:45
    once otherwise it is not a function
  • 00:14:48
    what do i mean by that if the vertical
  • 00:14:51
    line
  • 00:14:52
    hits two or more points on the graph
  • 00:14:55
    it is not considered a function
  • 00:14:59
    let's look at some examples look at this
  • 00:15:01
    graph
  • 00:15:02
    how would we know if this graph is a
  • 00:15:05
    function
  • 00:15:06
    or not again what's our magic keyword
  • 00:15:09
    we'll be using vlt that's the vertical
  • 00:15:13
    line test
  • 00:15:15
    right so that's it the blue line that
  • 00:15:18
    you see on the screen right now
  • 00:15:19
    that's an imaginary line yeah it's not
  • 00:15:22
    part of the graph
  • 00:15:23
    we just made that line to test if the
  • 00:15:26
    given graph
  • 00:15:27
    is a function or not i hope you're
  • 00:15:29
    following
  • 00:15:30
    so the point there is here which means
  • 00:15:34
    that the line the vertical line touches
  • 00:15:37
    the graph
  • 00:15:38
    at that point only once
  • 00:15:41
    now let's move the blue line let's move
  • 00:15:43
    the blue vertical line
  • 00:15:45
    because here you can check if it's a
  • 00:15:48
    function
  • 00:15:48
    if any point of the graph it would only
  • 00:15:51
    touch
  • 00:15:51
    the graph or the given graph once so
  • 00:15:54
    let's move the vertical line
  • 00:15:56
    how about there yes it only hits or it
  • 00:15:59
    only touches the graph once
  • 00:16:02
    how about there only once and finally
  • 00:16:05
    right here yes it only touches the graph
  • 00:16:08
    once hence we can say that the given
  • 00:16:11
    graph
  • 00:16:12
    is a function so that's an example of a
  • 00:16:15
    function
  • 00:16:16
    basing on the graph
  • 00:16:20
    let's look at another example identify
  • 00:16:23
    if this graph
  • 00:16:24
    is a function or not a function i'll
  • 00:16:27
    give you time
  • 00:16:28
    you may pause this video to give
  • 00:16:30
    yourself more time
  • 00:16:33
    all right are you done let's check let's
  • 00:16:36
    create
  • 00:16:37
    our imaginary vertical line again we
  • 00:16:39
    will be using
  • 00:16:40
    vertical line test right there
  • 00:16:43
    the black dot represents the point where
  • 00:16:46
    in the vertical line touches your given
  • 00:16:49
    wrath
  • 00:16:49
    it's only once right let's move it a
  • 00:16:52
    little bit to the right right there
  • 00:16:54
    it touches the graph how many times
  • 00:16:57
    still once
  • 00:16:58
    let's move it there still once
  • 00:17:02
    last one over there still it touches the
  • 00:17:05
    graph
  • 00:17:06
    once basing on that we can conclude that
  • 00:17:09
    the given graph
  • 00:17:10
    is indeed a function
  • 00:17:13
    so that's an example of a function now
  • 00:17:16
    let's practice more let's identify if
  • 00:17:19
    these given graphs
  • 00:17:20
    are functions or not a function again
  • 00:17:23
    let's identify
  • 00:17:25
    try these graphs you can pause this
  • 00:17:27
    video right now
  • 00:17:28
    and give yourself more time to
  • 00:17:30
    scrutinize each of the graph
  • 00:17:32
    and identify if it's a function or not
  • 00:17:36
    a function go ahead
  • 00:17:43
    [Music]
  • 00:17:45
    okay so let's reveal the answers
  • 00:17:49
    now based on the sixth graph we can
  • 00:17:51
    actually create
  • 00:17:52
    two groups and the first group consists
  • 00:17:55
    of
  • 00:17:56
    these two graphs
  • 00:17:59
    now let's focus on this point
  • 00:18:02
    right here for the first graph as you
  • 00:18:05
    can see
  • 00:18:05
    the vertical line touches the given
  • 00:18:07
    graph once
  • 00:18:08
    how about for the second graph there it
  • 00:18:11
    only touches
  • 00:18:12
    yes it touches the given graph same with
  • 00:18:15
    the first graph
  • 00:18:16
    only once let's try to move the vertical
  • 00:18:19
    line
  • 00:18:20
    to the right right there
  • 00:18:23
    it touches still the same once let's
  • 00:18:26
    move it more
  • 00:18:27
    right there still touch us once
  • 00:18:31
    and last one same result
  • 00:18:34
    once thus we can conclude that these two
  • 00:18:37
    graphs
  • 00:18:38
    are considered as
  • 00:18:41
    very good we consider this as functions
  • 00:18:47
    so the remaining four graphs looks like
  • 00:18:49
    this
  • 00:18:51
    observe for the first graph we have here
  • 00:18:54
    two points
  • 00:18:55
    which means that the vertical line
  • 00:18:57
    touches the graph or touches the given
  • 00:19:00
    graph
  • 00:19:00
    at two points however for the second
  • 00:19:03
    graph this would be the first one
  • 00:19:05
    and that would be the second one still
  • 00:19:07
    the same it touches the given graph
  • 00:19:09
    twice
  • 00:19:10
    the vertical line touches the graph here
  • 00:19:13
    at the same time here
  • 00:19:14
    so that means there would be two points
  • 00:19:16
    right and lastly we have here the last
  • 00:19:19
    graph it touches the graph
  • 00:19:22
    twice let's move the vertical line
  • 00:19:26
    like this well observe
  • 00:19:29
    that for the fourth graph you now have
  • 00:19:32
    three points
  • 00:19:33
    earlier it was only two this time as we
  • 00:19:36
    move the vertical line it touches the
  • 00:19:38
    graph at three points
  • 00:19:40
    now for the first three graphs it's the
  • 00:19:42
    same it touches the given graph twice
  • 00:19:45
    let's move it there observe
  • 00:19:48
    that in all these given graphs the
  • 00:19:51
    vertical line
  • 00:19:52
    touches the given graph more than once
  • 00:19:56
    again that's more than once because for
  • 00:19:59
    the first second and third graph
  • 00:20:01
    it touches the graph twice for the
  • 00:20:03
    fourth graph it touched us earlier the
  • 00:20:05
    graph twice
  • 00:20:06
    this time thrice it's more than once
  • 00:20:09
    yes which makes all of these graphs
  • 00:20:12
    not a function so these are examples of
  • 00:20:16
    not a function
  • 00:20:20
    so those are the illustrations again for
  • 00:20:23
    the mapping
  • 00:20:24
    sets and graph
  • 00:20:28
    how about functions in real life
  • 00:20:31
    this is a circle so an example of a
  • 00:20:34
    function in real life
  • 00:20:36
    is the circumference of a circle the
  • 00:20:39
    circumference of a circle
  • 00:20:41
    is a function of its diameter it can be
  • 00:20:43
    represented as
  • 00:20:45
    circumference or c of d is equal to d
  • 00:20:48
    pi alternatively we can also use it
  • 00:20:52
    as a function of radius which is c of
  • 00:20:55
    r is equal to two pi r
  • 00:20:59
    [Music]
  • 00:21:00
    another example is a shadow the length
  • 00:21:04
    of a person's shadow
  • 00:21:06
    along the floor is a function of their
  • 00:21:09
    height
  • 00:21:10
    and the third example is driving a car
  • 00:21:14
    when driving a car your location
  • 00:21:18
    is a function of time
  • 00:21:23
    what's more i prepared here a 10 item
  • 00:21:27
    assessment
  • 00:21:28
    first to check your understanding for
  • 00:21:30
    our lesson for today
  • 00:21:31
    let's try to have a closer look you can
  • 00:21:35
    pause this video or you can even take a
  • 00:21:37
    screenshot and answer it later during
  • 00:21:39
    your available time
  • 00:21:41
    so we have your items one two and three
  • 00:21:43
    again you may pause or take a screenshot
  • 00:21:46
    [Music]
  • 00:21:49
    okay let's move on the next set is for
  • 00:21:52
    items four to six
  • 00:22:00
    next we have seven to nine
  • 00:22:03
    again you may take a screenshot or pause
  • 00:22:06
    this video
  • 00:22:10
    and finally we have item number 10.
  • 00:22:14
    [Music]
  • 00:22:18
    if you're using the same mode you'll do
  • 00:22:20
    not forget to submit your answers to
  • 00:22:22
    your teacher on your agreed date and
  • 00:22:24
    time
  • 00:22:26
    [Music]
  • 00:22:27
    what you need to remember a relation
  • 00:22:30
    is a function when every x value is
  • 00:22:33
    associated to only one y value
  • 00:22:37
    do not forget that you can illustrate
  • 00:22:40
    functions
  • 00:22:41
    through graphing mapping or sets
  • 00:22:45
    and lastly functions can be seen in our
  • 00:22:48
    daily lives like driving a car
  • 00:22:51
    wherein your location is a function of
  • 00:22:54
    time
  • 00:22:54
    the length of your shadow which is a
  • 00:22:57
    function
  • 00:22:57
    of one's height and a lot more
  • 00:23:01
    and that's it we are done with the first
  • 00:23:03
    lesson
  • 00:23:04
    for this topic functions for our general
  • 00:23:07
    mathematics subject
  • 00:23:09
    great job for today see you in the next
  • 00:23:12
    lesson
タグ
  • mathématiques
  • fonctions
  • relations
  • domaine
  • portée
  • graphique
  • diagramme de correspondance
  • ensemble
  • test de ligne verticale
  • exemples de la vie réelle