The [img]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/16px-Menu_view_cas.svg.png[/img][i]CAS View[/i] allows you to use GeoGebra's CAS (Computer Algebra System) for symbolic computations.
Equations are entered using an equal sign =, while the input := indicates an assignment.
Put in the following Algebraic expressions to get in touch with the [i]CAS Input Bar[/i].
[table][tr][td][size=100]1. [b]= [/b][/size][/td][td][size=100]Enter the equation [code]3x + 5 = 7 [/code]using the simple [i]Equal[/i] sign into the [i]CAS Input[/i] [i]Bar [/i]and hit the [i]Enter[/i] key. [/size][/td][/tr][tr][td][size=100]2. [icon]https://wiki.geogebra.org/uploads/thumb/4/4d/Algebra_hidden.png/32px-Algebra_hidden.png[/icon][/size][/td][td][b]Note:[/b] If you want to show the corresponding line in the [img]https://wiki.geogebra.org/uploads/thumb/c/c8/Menu_view_graphics.svg/16px-Menu_view_graphics.svg.png[/img] [i]Graphics View[/i], click on the [i]Visibility [/i]button next to the equation. [/td][/tr][tr][td][size=100]3. [b]:=[/b][/size][/td][td][size=100]Enter the function [code]g(x) := 2 * x + 1[/code][code][/code] into the second row of the [img]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/16px-Menu_view_cas.svg.png[/img] [i]CAS View[/i] and hit the [i]Enter[/i] key.[br][/size][/td][/tr][tr][td][size=100][br][/size][/td][td][size=100][b]Hints: [/b][br][list][*]The function is automatically plotted in the [img]https://wiki.geogebra.org/uploads/thumb/c/c8/Menu_view_graphics.svg/16px-Menu_view_graphics.svg.png[/img] [i]Graphics View[/i].[/*][*]If you define[size=100] [code]g(x) := 2 * x + 1[/code][code] [/code][/size]in the [img]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/16px-Menu_view_cas.svg.png[/img] [i]CAS View[/i], then you can use[i] g(x)[/i] in all the other [i]Views[/i] of [i]GeoGebra[/i]. [br][/*][/list][/size][/td][/tr][/table]
In the [img]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/16px-Menu_view_cas.svg.png[/img] [i]CAS View[/i], you can use variables that were not assigned any value.
Solve an equation step by step.
[table][tr][td][size=100]1.[/size][/td][td][size=100][icon]https://www.geogebra.org/images/ggb/toolbar/mode_keepinput.png[/icon][/size][/td][td][size=100]Type [code]5x - 2 = 8[/code] and select the [i]Keep Input[/i] tool.[/size][/td][/tr][tr][td][size=100]2.[/size][/td][td][code]#[/code][/td][td][size=100]In row 2, type the shortcut [code]#[/code] to copy the previous output into the [i]CAS Input Bar[/i]. [br][/size][/td][/tr][tr][td][size=100]3.[/size][/td][td][size=100][icon]https://www.geogebra.org/images/ggb/toolbar/mode_evaluate.png[/icon][/size][/td][td]Type [code]+2[/code] next to [code]#[/code] and select the [i][i]Symbolic Evaluation [/i][/i]tool.[br][/td][/tr][tr][td][size=100]4.[/size][/td][td][size=100][code]#[br][/code][/size][/td][td]Copy again the previous output [code]5x = 10 [/code] into the next row.[/td][/tr][tr][td][size=100]5.[/size][/td][td][size=100][icon]/images/ggb/toolbar/mode_solve.png[/icon][/size][/td][td]Type [code]/ 5[/code] next to [code]#[/code] and select the [i][i][i]Symbolic Evaluation [/i][/i][/i]tool.[/td][/tr][tr][td][size=100]6.[/size][/td][td][size=100][icon]https://wiki.geogebra.org/uploads/thumb/4/4d/Algebra_hidden.png/32px-Algebra_hidden.png[/icon][/size][/td][td]In row 1, click on the disabled [i]Visibility [/i]button to display the original equation in the [img]https://wiki.geogebra.org/uploads/thumb/c/c8/Menu_view_graphics.svg/16px-Menu_view_graphics.svg.png[/img] [i]Graphics View[/i] and check your solution.[/td][/tr][/table][br][b]Note: [/b][br][list][*][code]#[/code] copies the previous output.[/*][*][code]#3[/code] copies the output of row 3.[/*][/list]
Multiplication of variables needs to be marked explicitly using an asterisk [code]*[/code] or with a space. [br][b]Example:[/b] The input [code]b * (c + d)[/code] gives you the output [i]bc + bd[/i].[br][br][b]Note:[/b] If you enter bc without the asterisk or a space between the factors, you will create a new variable called bc.