Quick Tour of the TI-83. Teachers Teaching with Technology. Scotland T 3. Teachers Teaching with Technology (Scotland)

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1 Teachers Teaching with Technology (Scotland) Teachers Teaching with Technology T 3 Scotland Quick Tour of the TI-83 Teachers Teaching with Technology (Scotland)

2 Quick tour of Home Screen A Quick Tour of the Ti-83 Graphing Calculator Important keys QUIT ENTER ALPHA CLEAR 2nd MODE These are known as cursor keys and are used to navigate through the menus but in the initial stages these are best used to set the screen contrast. Setting the contrast : press 2nd repeatedly to darken the screen (Darkest 9) press 2nd repeatedly to lighten the screen (Lightest 0) ENTER Perhaps the most important key on the TI-83. It is used to drive any new action e.g. run a program or store a variable. On the home screen it is the equivalent of the = button on scientific calculators. Ex. 3+4 ENTER gives CLEAR If p ressed before the ENTER it will clear the current line of the home screen. Pressed after the ENTER, clears the screen. Ex. press CLEAR gives ALPHA Used to enter letters rather than numbers Ex ALPHA TEST A MATH gives QUIT MODE This is used to return to home screen from other menus. T3 Scotland TI-83Quick Tour Page 1 of 8

3 Quick tour of the Mode Screen The mode screen is used to set up the calculator for any particular application. To get the mode screen: QUIT Press MODE gives Sets the type of number required. Sets the degree of accuracy required. Sets the type of angle required. Sets the type of function used. Sets the type of graph plot used. Sets mode of graphing. Sets type of number used. Sets type of display required. Important details to note Float Often ignored, but can be resp onsible for errors and difficulties. Best left in Float. Radian Degree Care required when zooming and if exact radian answers required. Func Par Pol Seq Full Horiz G-T Usually at fault when normal grap hs can t be drawn. Usually set to Func Very useful for disp laying Home screen calculations with a grap h and/or tables with graphs. T3 Scotland TI-83Quick Tour Page 2 of 8

4 Graphing Important Keys Y= WINDOW ZOOM TRACE GRAPH Y= Gives the grap hing menu shown and is the method of entering functions to be graphed WINDOW Gives the screen shown and is used to enter the range over which we want to grap h. Notice the range here may not be that shown on your machine ZOOM Gives the menu screen shown. Each one is a pre-defined window range. TRACE This keys accesses the numerical values on the graph screen GRAPH This key is used after entering a function when we want to see the graph. Gives access to the screen shown 2nd FORMAT ZOOM Sets the cursor coords shown in rect or pol coords. Sets coord display on or off. Sets coord grid on or off. Switches the axes on or off. Switches axes labels on or off. Switches function on or off on the graph. T3 Scotland TI-83Quick Tour Page 3 of 8

5 Teacher Hints Window Ranges For most situations met in the Scottish syllabuses the most useful control functions are: ZStandard ZDecimal ZTrig ZSquare Zoom Stat The Format screen is usually best set as shown occasionally Whenever we start mixing menus we can get strange results. Knowing the behaviour of functions beforehand and testing for ap p rop riate Window ranges is the only method of guaranteeing the result! Example Enter the function shown Set Format. ZStandard gives. Use Trace gives. Better Trace values are obtained using ZDecimal. T3 Scotland TI-83Quick Tour Page 4 of 8

6 Teacher Hints Trigonometric Graphs Trigonometric grap hs bring into conflict radians and degrees. It is imp ortant to establish which you are working using the mode screen before commencing. In degrees ZTrig gives window range In radians Ztrig gives Both will give the correct grap h but not the desired results when Trace ing It is important to note that ZTrig gives an ideal window range for picking off values using trace as it relates the function to the number of pixels on the screen. (Each pixel on the x-axis becomes 7½ or (π / 24)radians). That is why it does not range to 360. We can modify the range after zooming to allow us from 0 to 352 and if we trace p ast these values we get consistent answers. Example Enter Y = sin(x) Use ZTrig in degrees Now reset the window range Xmin=0 Ymin=-1.5 Ymax=1.5. Use trace to find values of Y when X=360 and when X=-90 T3 Scotland TI-83Quick Tour Page 5 of 8

7 Table Function (How to obtain Tables of Values) Having entered a function into the Y= menu it is possible to see tables of values for this function using the TABLE 2nd GRAPH key. First enter the function Y = 2X To do this press 2nd TABLE GRAPH to see a table. Your table may be different as we may have tables set to different settings, to see these settings press 2nd TBLSET WINDOW to see In this Table Setup Window we can alter the starting X-value and the step size for the table. X = -2 and are going up in steps of 1. T3 Scotland TI-83Quick Tour Page 6 of 8

8 Teachers Hints Evaluating functions There are many ways to do this From a graph Advantages are it is quick and easy and usually we are at that screen when we want values. Disadvantages are that unless we have a good range the values may not give the answers we want. From a Table Advantages are we get what we ask for by using the Tblset and have some control over accuracy. Disadvantages are we may wish to relate this to more than one graph, or decimal values not suitable. On the Home screen This can be done as shown. Press 2 STO XT n,,, ALPHA i 2 XT,,, n ENTER Any expression can be evaluated this way. Using Y-Vars If the expression is entered in the Y= menu then we can evaluate it using the Yvars menu. Press VARS to get Press to get T3 Scotland TI-83Quick Tour Page 7 of 8

9 Press either 1 or ENTER to get Press either 1 or ENTER to get Use brackets and the value you want inside them Press ENTER to see the result Advantages are that if we wish to evaluate many x 2nd ENTER values we can use to get the Y variable back Disadvantages are that it is a lot of key work if we only want 1 value T3 Scotland TI-83Quick Tour Page 8 of 8