## Creating an Equation

- Position the cursor where you want the equation to appear in the question or narrative.
- Click Insert from the menu bar and select Equation.
The Equation Editor window opens. You will see a flashing cursor in a dotted box.

The box represents a slot. An equation is composed of one or more slots which contain numbers and mathematical symbols. Although the simplest of equations, like the one introduced above (3+4=7), might contain only one slot, most equations contain multiple slots which, when arranged by the equation editor, form an equation.

There are two toolbars across the top of the screen. The topmost toolbar (as presented below) shows a variety of operators, mathematical symbols, Greek characters, and character accents.

Under the symbol toolbar, you can see the template toolbar (as shown below). A template is used to arrange slots to form parts of a mathematical equation. One such template would represent a stacked fraction, where one slot would contain the numerator, one slot would contain the denominator, and there would be a fraction line in between the two slots.

In addition to the toolbars, you can use the Zoom, Alignment, Style, and Size menus to manipulate elements of the equation.

- For practice, enter the simple equation (3 + 4 = 7). Key the following into the empty slot: 3+4=7

**NOTE**You do not need to press the space bar in between any of the characters when you are keying an equation using Math style. All spacing is done for you to conform to mathematical style conventions. You can adjust any of the spacing amounts for a particular equation or for all future equations using the Equation Preferences option. The different styles are discussed under the Style menu topic.

- The equation could be recorded at this point. Since we are just practicing, click Edit and select Select All and then click Edit and select Clear to remove this equation. All of the edit menu features (Undo, Cut, Copy, Paste, etc.) are available to you as you enter or edit equations.
- You should try to enter a more complicated equation. Begin by keying the following: sinx=
You will notice as you key "sin" that the characters change from italic to plain text when you key the "n". The equation editor is set up to recognize various function names (sin, cos, tan, log, etc.) and to show them a little differently. Variable names, such as "x" in our example, are shown in italic (by default). By doing this, a great deal of time can be saved from formatting the equation by hand. Also, notice that the spacing has been done for you.

- To enter the summation sign and set the equation up to enter the limits above and below the summation sign, we need to enter a summation template. This can be done by clicking on the summation template button and choosing the option Summation with underscript and overscript limits or we can simply press Ctrl+E.

**TIP**Ctrl+E is the keyboard shortcut to enter this particular summation template.

When you press Ctrl+E, the program creates three empty slots. The primary slot appears just to the right of the summation sign along with two limit slots, above and below the summation sign. Your screen should look like this:

- Leave the primary slot (to the right of the summation sign) empty for a moment and press the Tab key. Notice that the cursor has moved to the slot below the summation sign. You can use the Tab key at any time while entering or editing an equation to move between slots.
- Key the following into the lower-limit slot: k=0
Remember that you do not have to press Enter (PC) or Return (Mac) after you key text.

- Press the Tab key again to position the cursor in the upper-limit slot.
- Press Ctrl+K, release both keys and press the I key (as in Infinity). The infinity symbol is inserted into the top slot.
- Press Shift+Tab two times to return to the primary slot. You could also have pressed the (right arrow) key once or simply used the mouse and clicked in the right most slot.
- Now we need to create another template, this time a stacked fraction. Press Ctrl+F (again, a shortcut key to create a Fraction). Your screen should look like this:
- Key the following into the numerator: (-1)
- Insert the superscript template. PC users can create a superscript by pressing Ctrl+H (for High). A smaller slot is created up and to the right of the (-1).
- Key the following into the superscript: k
- If you continued to key text at this point, it would also be inserted into the superscript. To exit the superscript slot, press the Tab key once.

**TIP**Notice that the flashing cursor has a vertical part to show you where you will be keying. It also has a horizontal part (underline) that shows you in which slot keyed text will be inserted. This is a good guide to keep track of where you are in an equation.

- Press the Tab key again to position the cursor in the denominator of the fraction. Again, there are multiple ways to position the cursor in this slot. You can also use the up and down arrow keys to navigate between slots.
- Key the following into the denominator: (2k+1)!
- Press the Tab key once to move from the denominator slot back to the primary summation slot and key the following: x
- Insert a superscript template (Ctrl+H for PC) and key the following as the superscript: 2k+1
- Press the Tab key again to exit the superscript slot. Your screen should look like the following:
- Again, check the underline cursor to determine if you are in the correct slot. The underline should go under the entire equation at this point (meaning that you are in the "master" slot).
- We need to type some spaces at this point and the textual phrase "for every". To do this, press Ctrl+T (for Text style). Notice that the Style menu changes to "Text".
- Press the space bar four times and key the following: for every
And press the space bar one more time.

- Press Ctrl+M (for Math style) and key the following: x
- Return to text style (Ctrl+T) and press the space bar, the word "in", and press the space bar one last time.
- To key the mathematical symbol at the end, press Ctrl+K, release both keys, and press Shift+R.
- Complete the equation by keying the "." at the end. The equation you keyed should match the one shown above. If it does not, review the steps above and the more specific help topics for each of the features.
- Record the equation by clicking the Record button.
- To edit an existing equation:
- Double-click on the equation you want to edit, or highlight the equation, click Format from the menu bar and select Format Equation.
- Use all of the tools shown above and in the other equation editor help topics to modify the equation as needed.
- Click Record when you are finished.

- To delete an equation highlight the equation you want to delete, click Edit from the menu bar and select Clear.
- To display the equation only if the value of a certain variable is True, enter the variable in the field following Display equation (only if).