Activity 1

Click the "Standard Equations" tab. 

For equation 1, type the expression x.  Notice that the box in the "Show Graph" column becomes checked automatically.  You can uncheck the box later if you do not want to show the graph of y=x.

For equation 5, type the expression sin(x).  Click the "Plot Graphs" button.

Click "Close".  Click the checkmark for equation 1 to uncheck the box.  Click "Plot Graphs".  Now only the graph of equation 5 is displayed.  Now display both graphs again.  Notice that the two graphs nearly correspond for small values of x.  (Recall that sin(x) ≈ x for small values of x.)

How close are the two values?

Click "Close" to return to the equation screen.  Click "Show Tables".  The tables shown represent values of the expressions.  The tables are numbered on top and labeled with their expressions at the bottom.  We want to visually compare the two lists, but they are too far apart to easily make the comparison.  Click "Swap Lists" and follow the instructions.  ("Swap Lists" is provided as a reminder.  You can click the numbers above two lists at any time to swap the lists without first clicking "Swap Lists".)  In this case, we want to swap lists 2 and 5 so that the two lists of numbers are side-by-side.  Click the numbers above the lists to swap 2 and 5.  Notice that the numbers above the lists are swapped, too so you can tell which equation number corresponds to a list.

Now we can compare values more easily, but we want to compare for values of x close to zero, and the listed values of x are too big.

Double-click the white box just right of the "∆ Table" label.  Change the "1" to ".05".  The table values should change immediately to reflect your request.  Now double-click the white box just right of the "Table Minimum" label.  Change "0" to "-.25" and watch the changes in the lists.

Click "Hide Tables"..  Clear all equations.  Click "Plot Graphs".

Click "Points" in the menubar and then "Add".  Position the mouse crosshair at a location of your choice and left-click.  (You do not have to be exact; if you are reasonably precise, points close to lattice points will be interpreted by students as lattice points.)

Click "Notes" on the menubar and select "Add".  Type "A" in the input box and press ENTER or click "OK".  The letter "A" will be placed at the current location of the mouse pointer.  Repeat the process to create point B.  Plot a third point.  Then click a location to the left and above the point.  Then label the point C.  Notice that the label "C" was placed at the location of your click.  (Actually, you must imagine the letter contained inside a rectangle, and the upper left corner of the rectangle is placed at the clicked location.)

Select a location to print instructions for the graph.  Click that location.  Click "Notes" and select "Font Size".  Select 18 and click "OK".  Click "Notes" and select "Add".  In the inputbox, type, "Find the equation of the line through points A and B." (without the quotation marks) and press ENTER.  You have just created a problem with a built-in question that can be used in a worksheet or test.  The question can also be asked as part of a word processing document instead of part of the graphic.

Now we will save this problem to the clipboard and place it inside a Word document.

From the menubar, select File - Save - Save Selection - ... to the Clipboard.  During the process, notice the options that are available.  A pop-up message will tell you what to do. 

Use the standard method of selecting something with a mouse, i.e., left-click the upper-left corner of an imaginary rectangle that encompasses the object; drag the mouse to the lower-right corner of that rectangle; release the mouse button.  Your selection is now on the clipboard.

Use Alt-Tab to navigate to your open Word document or open a new Word document.  Click the "Paste" button on the toolbar or under "Edit" from the menubar.  Your graphic should appear on your document.   If you click on your graphic, handles will appear around it, and you can resize it as desired.

It will take experience to know how dark to make the gridlines for your printer and copier.  Use the darkness slider to adjust darkness.  My experience shows that you must set the darkness darker than you want the final result to appear.

Options under "Layout" in the menubar enable you to use gridlines, lattice points, or neither in displaying graphs.

The "Erase" button in the Vertical Line frame will erase all vertical lines, points and notes.

 

 

 

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