The [img]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/16px-Menu_view_cas.svg.png[/img] [i]CAS Perspective[/i] includes 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 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] By default, the [img]https://wiki.geogebra.org/uploads/thumb/7/7d/Stylingbar_graphicsview_show_or_hide_the_axes.svg/16px-Stylingbar_graphicsview_show_or_hide_the_axes.svg.png[/img] [i]coordinate axes[/i] are shown 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]. Depending on which of these [i]Views[/i] is activated, either the [i]Graphics View Toolbar[/i] or the [i]CAS View Toolbar[/i] are shown at the top of the app[size=100], with the [img]https://wiki.geogebra.org/uploads/thumb/3/38/Menu-edit-undo.svg/16px-Menu-edit-undo.svg.png[/img] [img]https://wiki.geogebra.org/uploads/thumb/8/85/Menu-edit-redo.svg/16px-Menu-edit-redo.svg.png[/img][size=100] [/size][i]Undo / Redo[/i] buttons in the top right corner.[/size]
[size=100]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. It consists of cells with an[i] Input Bar[/i] at the top and the output displayd below it. You can use this [i]Input Bar [/i]the same way as the normal [i]Algebra View Input Bar[/i], with the following differences:[br][br][/size][list][*][size=100]You can use variables that were not assigned any value.[br][b]Example:[/b] Enter [code](a+b)^2[/code] and select the [icon]https://www.geogebra.org/images/ggb/toolbar/mode_expand.png[/icon] [i]Expand [/i]tool. You will get the output [i]a²+2ab+b²[/i].[br][br][/size][/*][*][size=100]Equations are entered using an equal sign [code]=[/code] (e.g. [code]y = 2*x[/code]), while the input [code]:=[/code] indicates an assignment (e.g. [code]f(x) := 2*x[/code]). [br][b]Note[/b]: This means that the input [code]a = 2[/code] will not assign value [i]2[/i] to the variable [i]a[/i]. [br][br][/size][/*][*][size=100]Multiplication needs to be marked explicitly using an asterisk [code]*[/code] or a space between the factors.[br][/size][/*][/list][size=100][br][b]Note:[/b] The [img]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/16px-Menu_view_cas.svg.png[/img] CAS View offers a selection of keyboard shortcuts that help you to evaluate or check your input, as well as to reuse previous input or output in a new row[/size].
Get in touch with the [img]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/16px-Menu_view_cas.svg.png[/img] [i]CAS Perspective[/i] by following the instructions below.
[table][tr][td][size=100]1.[/size][/td][td][size=100][icon]https://wiki.geogebra.org/uploads/thumb/4/47/Menu_view_cas.svg/32px-Menu_view_cas.svg.png[/icon][/size][/td][td][size=100]Enter [code](x - 2) (x + 1)[/code] into the [i]Input Bar[/i] 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 try out the different evaluation options:[/size][/td][/tr][tr][td][size=100]2.[/size][/td][td][size=100][icon]https://www.geogebra.org/images/ggb/toolbar/mode_evaluate.png[/icon][/size][/td][td][size=100]Evaluate your input using the [i]Symbolic Evaluation [/i]tool.[br][b]Note:[/b] Your expression is simplified and displayed as [code]x² - x - 2 [/code]in the output display.[/size][/td][/tr][tr][td][size=100]4.[/size][/td][td][size=100][icon]/images/ggb/toolbar/mode_keepinput.png[/icon][/size][/td][td][size=100]Keep your input using the [i]Keep Input[/i] tool.[br][b]Note:[/b] Your expression is not changed and will be displayed as[code] (x - 2) (x + 1) [/code]in the output display.[br][/size][/td][/tr][tr][td][size=100]5.[/size][/td][td][size=100][icon]/images/ggb/toolbar/mode_keepinput.png[/icon][/size][/td][td][size=100]Create a quadratic polynomial by entering f(x):= x^2 – 3/2 * x + 2 into the first row and select the [i]Keep Input[/i] tool instead of pressing the [i]Enter[/i] key.[/size][/td][/tr][tr][td][size=100]6.[/size][/td][td][size=100][/size][/td][td][size=100][b]Note:[/b] If you want your entered expression not to be changed in any way, choose the tool before entering it.[/size][/td][/tr][tr][td][size=100]7.[/size][/td][td][size=100][icon]/images/ggb/toolbar/mode_factor.png[/icon][/size][/td][td][size=100]Enter f(x) into the second row and select the [i]Factor[/i] tool to find the factors of the function.[/size][/td][/tr][tr][td][size=100]8.[/size][/td][td][size=100][icon]/images/ggb/toolbar/mode_derivative.png[/icon][/size][/td][td][size=100]Enter f(x) into the third row and select the [i]Derivative[/i] tool to calculate the derivative of the function.[/size][/td][/tr][tr][td][size=100]9.[/size][/td][td][size=100][icon]https://www.geogebra.org/images/ggb/toolbar/mode_showhideobject.png[/icon][br][/size][/td][td][size=100][b]Hint:[/b] You can display the function 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] by clicking on the [i]Visibility [/i]button below the corresponding row number 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].[br][/size][/td][/tr][/table]