# Display Equations in a Table on the TI-83 Plus

After you have entered the parametric equations into the TI-83 Plus graphing calculator, you can have the calculator create a table of the terms in all pairs of parametric equations in the Y= editor that are defined with a highlighted equal sign. To create a table:

Highlight the equal sign of those parametric equations in the Y= editor that you want to appear in the table.

Only those parametric equations in the Y= editor that are defined with a highlighted equal sign will appear in the table. To highlight or unhighlight an equal sign, press

**[Y=]**, use thekeys to place the cursor on the equal sign in the definition of either equation in the pair of parametric equations, and then press

**[ENTER]**to toggle the equal sign between highlighted and unhighlighted.Press [2nd][WINDOW] to access the Table Setup editor.

Enter a number in TblStart and then press [ENTER].

**TblStart**is the first value of the independent variable**T**to appear in the table.To enter the number you have chosen for

**TblStart**, place the cursor on the number appearing after the equal sign, press the number keys to enter your number, and then press**[ENTER]**.Enter a number in

**and then press [ENTER].**gives the increment for the independent variable

**T**. You usually want to setequal to a small number like 0.5, 0.1, or 0.01.

To enter the number you have chosen for

place the cursor on the number appearing after the equal sign, press the number keys to enter your number, and then press

**[ENTER]**.Set the mode for Indpnt and Depend.

To change the mode of either

**Indpnt**or**Depend**, use thekeys to place the cursor on the desired mode, either

**Auto**or**Ask**, and then press**[ENTER]**.To have the calculator automatically generate the table for you, put both

**Indpnt**and**Depend**in**Auto**mode.If you want to create a user-defined table that contains only those values of the independent variable

**T**that you specify — and then have the calculator figure out the corresponding values of the parametric equations — put**Indpnt**in**Ask**mode and**Depend**in**Auto**mode. Step 6 explains how you construct such a table.For a user-defined table, you don’t have to assign values to

**TblStart**andin the Table Setup editor.

The other combinations of mode settings for

**Indpnt**and**Depend**are not that useful when you’re dealing with parametric equations.Press [2nd][GRAPH] to display the table.

When you display the table,

**Indpnt**and**Depend**in Step 5. And what you can do with the table also depends on these modes. Here’s what you see and what you can do:**For an automatically generated table:**If

**Indpnt**and**Depend**are both in**Auto**mode, then pressing**[2nd][GRAPH]**generatesuntil those rows appear. Likewise, repeatedly press

to display rows above the first row on the screen.

Each time the calculator redisplays a table with a different set of rows, it also automatically resets

**TblStart**to the value of**T**appearing in the first row of the newly displayed table. To return the table to its original state, press**[2nd][WINDOW]**to access the Table Setup editor, and then change the value the calculator assigned to**TblStart**.If you’re constructing a table for more than one pair of parametric equations, only the first pair will appear on the screen. To see another pair of equations, repeatedly press

until they appear. This causes the first pair of equations to disappear. To see them again, repeatedly press

until they appear.

**For a user-generated table:**If you put

**Indpnt**in**Ask**mode and**Depend**in**Auto**mode so that you can generate your own table, then the table should be empty when you display it. If it’s not, clear the table.In an empty table, key in the first value of the independent variable

**T**you want to appear in the table, and then press**[ENTER]**. The corresponding values of the first pair of parametric equations automatically appear.Key in the next value of

**T**you want in the table and press**[ENTER]**, and so on. The values for**T**that you place in the first column don’t have to be in any specific order, nor do they have to be between**Tmin**and**Tmax**.