Texas Instruments TINSPIRECX manual Tracing Graphs, Points and coordinates, Points of intersection

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Tracing Graphs

Press b51 to choose the Graph Trace option.

Notice the Trace icon in the top left

corner of the work area. This is typical of many of the options from the menus.

Press ¡ and ¢ to trace along the graph and see the coordinates of current points in the lower right corner. For intricate functions progress can be slow along the curve but you

can change the Trace Settings to increase the Trace Step: press b53 and try a step of 0.5 or 1. To start tracing at an integer value of x, in Graph Trace mode simply type the integer and press ·.

Press £ or ¤ to move to the other graph. To trace through all the visible functions at once use Trace All b52. Notice that significant points such as maxima, minima and zeros are automatically identified.

To stop tracing you need to press d. Check to see that the Trace icon is no longer showing in the top left corner.

Points and coordinates

Here is the way to mark points of intersection of two lines.

•Press b73 to choose the Intersection Point(s) option. Notice the icon has appeared in the top left corner.

•Move the cursor to the graph of f1(x). With the graph highlighted click x.

•Move to the graph of f2(x). With the graph highlighted click x.

Notice that the Intersection Points icon is still visible so you can go on to mark more intersections. For example you could try marking where the two graphs cross the y-axis.

Now press d.

First Steps with TI-Nspire™

Tutorial 4: Graphing

Trace picks out significant points

The current value of the trace is displayed in the bottom corner

Points of intersection

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© 2012 Texas Instruments Education Technology

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Contents First Steps About this document Contents Appendix TI-Nspire CX Keypad Layout TI-Nspire Documents Nothing on the screen?Memory Battery Life Charging the handheldHome Screen First Steps with TI-Nspire Tutorial 1 TI-Nspire documents Documents, Problems and Pages ScratchpadNavigating Documents First Steps with TI-Nspire Tutorial 1 TI-Nspire documents Contextual Menus Check list of some key points in Tutorial Calculator Application Basic operationsHistory Lesson Approximate CalculationsTemplates Menu of maths templatesDocument settings dialog box Effect of changed settingsGetting Set Some Algebra Ways to define variablesUse of function notation Calculator Menu Statistical Distribution TablesLists of random integers Variables Linked to Documents List of defined variablesWhy use Notes? Making NotesVarious text formatting Instructions Recording results Splitting the Screen Format sub-menuWays to split the screen You must press /e and then b Interactive Notes An inserted comment Use of proof template and symbolsMore Options from the Notes Menu Use of Q+A templateAsking Questions Check list of some key points in Tutorial Graphing Functions GraphingGraphs & Geometry Two Views Graphing ViewOpen-hand cursor Grab and Drag PracticeChanging the Axes Grabbed tick mark on the axesZoom settings Grabbed-sheet icon Editing, Deleting or Hiding a FunctionChanging f2 in the function history Trace picks out significant points Tracing GraphsPoints and coordinates Points of intersectionAnalyse Graph Menu Coordinates and labelled pointsUsing Sliders Manually Moving GraphsAlternative icons Transformed graph and equation Sequence Plotting Check list of some key points in Tutorial Two Parallel Lines GeometryView for Plane Geometry Drawing the base of the triangleWhat’s grabbable? Construct the TriangleMany options in the Construction menu Measurement menu Making MeasurementsVariables and Text Storing the measurement as a variableReady to grab a and slide it Tidying Up and Using AttributesDynamic Changes Changing the attributes of the triangleArea is now locked Unlocked/Unpinned Points B and C. Try Moving point BCheck list of some key points in Tutorial Lists & Spreadsheet Entering Data as ListsUsing Formulae Conflict resolutionOne way to enter a formula Typical Spreadsheet Actions Capturing Data Function TablesHand-made function table Simple function table Options for function tables Graph and table side by sideFrequency Charts Charts with One Variable One and Two Variable StatisticsShoe Sizes and Hand Spans Comparing Boxplots Charts for Categorical DataPie Chart displaying categorical data Upper quartile displayedCharts with Two Variables Fitting a Line by Hand and EyeReady to add a 2nd variable Drawing the Regression Line Getting the StatsCalculated regression line Statistics Calculations menu Sets of statistics Dragging on the ChartsWorking with Frequency Data Effect of moving a point from here … … to hereTexas Instruments Education Technology Check list of some key points in Tutorial Multiple Representations Draw and Measure a CircleMeasured circle Two Scatterplots Setting up a scatter plot Data capture is under waySpreadsheet for Data Capture Collecting Just a Little DataLinear relationship Go to Town with Data CollectionFit a Straight Line Moving a straight line by hand Not a linear relationshipDifferent Approach to Scatterplots RegressionBasic quadratic ready for fitting… … and dragged into place