1) quadratic functions

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To explore the properties of quadratic functions and their graphs. To investigate the different forms in which quadratic functions can be expressed. To explore the transformations of quadratic functions and their graphs. http://www.youtube.com/watch?v=VSUKNxVXE4E&feature=player_embedded# http://evmaths.jimdo.com/year11/functions/?logout=1

Transcript of 1) quadratic functions

  • Toexplorethepropertiesofquadraticfunctionsandtheirgraphs.

    Toinvestigatethedifferentformsinwhichquadraticfunctionscanbeexpressed. Toexplorethetransformationsofquadraticfunctionsandtheirgraphs. http://www.youtube.com/watch?v=VSUKNxVXE4E&feature=player_embedded#

    http://evmaths.jimdo.com/year11/functions/?logout=1

  • Ifa,bandcarerealnumbersanda0,thenthefunctionf(x)=ax2+bx+cisaquadraticfunction.

    theexpressionax2+bx+cisapolynomialofdegree2

    a,bandcarecoefficients

  • Thegraphofaquadraticfunctionisaparabola.

    Whatisthegraphofaquadraticfunction?

    UseyourGDCtoplotthegraphoff(x)=2x28x+1

  • UseyourGDCtoplotthegraphoff(x)=2x28x+1

    1)selectmenuGraph

    2)imputtheformula

    usethisbuttonforvariable''x''

  • UseyourGDCtoplotthegraphoff(x)=2x28x+1

    3)pressEXEtoentertheformula

    4)PressF6toDRAW

    5)Adjustthewindowtoviewthewholegraph.(F3)

  • vertex

    Aparabolahasasingleturningpointthatiscalleditsvertexandalineofsymmetrythatpassesthroughthevertex

    lineofsymmetry

  • Youcanuseyourcalculatortofindthevertexofaparabola

    Forthisparabolathevertexisitsminimumvalue

    Vertexisthepoint(2,7)

  • Youaregoingtoinvestigatetheeffectthatthecoefficientshaveonthegraphofaparabola.

    Useyourcalculatortosketchthegraphofthefollowingfunctions:

    y=x2 y=x2+3 y=x22

  • NowyouaregoingtoworkwithdynamicgraphsbyusingslidersinGeoGebra.

    Verifyyourconclusionusingasliderkandy=x2+k.

    Verticaltranslationofparabola.ggb

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

  • Sketch the graphs of and

    y=x2

    y=x22

    y=x2+3

    vertex:

    lineofsymmetry:

    vertex:

    lineofsymmetry:

  • Conclusions:

    parabola moves upwards

    parabola moves downwards

    vertex:

    line of symmetry:

    (0,k)

    x=0

    Translationk units along yaxis

    k>0

    k

  • UseGeoGebratoplotthefollowinggraphs:

    Verifyyourconclusionusingasliderhandy=(xh)2.

    y=(x2)2 y=(x+3)2y=x2

  • Consider the graphs of

    vertex:

    lineofsymmetry:

    vertex:

    lineofsymmetry:

    y=(x+3)2

    y=(x2)2

    y=x2

    and

    What can you say about vertex and symmetry line?

    Horizontaltranslationofparabola.ggb

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

  • Conclusions:

    parabola moves to the right

    parabola moves to the left

    vertex:

    line of symmetry:

    vertex:

    line of symmetry:

    (h,0)

    x=h

    (h,0)

    x=h

    Translation alongxaxis

    (h>0)

  • Wherewouldyouexpectthevertexofy=(x4)2+5tobe?

    Describetheshapeandthepositionofthegraphofy=(xh)2+k.

    Translationsinparabola.ggb

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

  • Conclusions:

    vertex

    (h,k)

    (h,k)

  • Consider,and

    y=x2 y=2x2

    vertex:

    lineofsymmetry:

  • Whatdoyouexpectif?

    y=x2

    y=x2

    vertex:

    lineofsymmetry:Verticalstretchofparabola.ggb

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

  • Conclusions:

    y=ax2Thegraphof isaparabolawithvertex: (0,0) lineofsymmetry: x=0

    a>0 a1 as"a"increasestheparabolagets"thinner"

    0

  • y=(x1)2+3

    vertex:

    line of symmetry:

    (1,3)

    x=1

  • y=2(x3)2

    vertex:

    line of symmetry:

    (3,0)

    x=3

  • y=3x2+4

    vertex:

    line of symmetry:

    (0,4)

    x=0

  • y=3(x+1)22

    vertex:

    line of symmetry:

    (-1,-2)

    x=-1

    http://members.shaw.ca/ron.blond/QFA.CSF.APPLET/index.html

    TransformacionesFuncinCuadrtica.ggb

    geogebra_thumbnail.png

    geogebra.xml

    SMART Notebook

  • For

    Parabolas of the form

    Whatistheyintercept?

    Findtherootsoff.

    Concavity?

    factorising (if possible) by formula

    (y=0)

    =0

  • yintercept=8

    roots:4and2

    lineofsymmetry?

    vertex?

  • Line of symmetry is in the middle between the roots :

    The vertex will be on the line of symmetry:

    We can find the line of symmetry by doing :

    y - intercept: (0,c)

    a0

    Cambioscuadratica.ggb

    geogebra_thumbnail.png

    geogebra.xml

    SMART Notebook

  • For find:

    y- intercept:

    line of symmetry:

    vertex:

    roots:

    Now draw a sketch of the function.

  • y- intercept: line of symmetry:

    vertex: roots:

    Now draw a sketch of the function.

    Express f(x) in the form

  • y=a(xx1)(xx2)Parabolas of the form :

    y=(x3)(x+1)

    Roots:

    Lineofsymmetry:

    Vertex:

    In general:

    x1andx2

  • axisofsymmetry

    vertex

    root

    root

    yintercept

    (0,c)

  • http://www.univie.ac.at/future.media/moe/tests/fun1/erkennen.html

    Solveworksheet:Quadraticfunctions

    Attheendofthelesson:QUADRATICFUNCTIONSI2010.doc

    Y11 SL EV

    QUADRATIC FUNCTIONS

    1) Complete

    2) Find the minimum value of

    3) i) Factorize

    ii) Determine the integer values for which

    is less than zero.

    4) a) Factorise

    b) Sketch the graph of

    5) Complete

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    _1253110198.unknown

    _1253110703.unknown

    _1253111211.unknown

    _1253111262.unknown

    _1253111347.unknown

    _1253111234.unknown

    _1253110752.unknown

    _1253110501.unknown

    _1253110535.unknown

    _1253110347.unknown

    _1253110085.unknown

    _1253110145.unknown

    _1253109960.unknown

    _1253110010.unknown

    _1253109856.unknown

    SMART Notebook

  • y=(x2)2

    y=x2+1

    y=x22

    y=x2+3

    y=(x3)2+5

    y=2x2+1

  • Slidetoprint:

  • Attachments

    Parabolacanonica.ggb

    Cambioscuadratica.ggb

    QUADRATICFUNCTIONSI2010.doc

    TransformacionesFuncinCuadrtica.ggb

    Verticaltranslationofparabola.ggb

    Verticalstretchofparabola.ggb

    Horizontaltranslationofparabola.ggb

    Translationsinparabola.ggb

    geogebra_thumbnail.png

    geogebra.xml

    SMART Notebook

    geogebra_thumbnail.png

    geogebra.xml

    SMART Notebook

    Y11 SL EV

    QUADRATIC FUNCTIONS

    1) Complete

    2) Find the minimum value of

    3) i) Factorize

    ii) Determine the integer values for which

    is less than zero.

    4) a) Factorise

    b) Sketch the graph of

    5) Complete

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Vertex:

    Line of symmetry:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    Roots:

    Line of symmetry:

    Vertex:

    y-intercept:

    EMBED Equation.DSMT4

    _1253110198.unknown

    _1253110703.unknown

    _1253111211.unknown

    _1253111262.unknown

    _1253111347.unknown

    _1253111234.unknown

    _1253110752.unknown

    _1253110501.unknown

    _1253110535.unknown

    _1253110347.unknown

    _1253110085.unknown

    _1253110145.unknown

    _1253109960.unknown

    _1253110010.unknown

    _1253109856.unknown

    SMART Notebook

    geogebra_thumbnail.png

    geogebra.xml

    SMART Notebook

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

    geogebra_thumbnail.png

    geogebra_javascript.js

    function ggbOnInit() {}

    geogebra.xml

    SMART Notebook

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