Make a table of values for a function

Calculate a sequence of f(x) values over a chosen range without re-entering the expression.

3 étapes

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When you need values for sketching a graph or checking a few points, re-entering the entire expression for each $x$ is slow. For example, find the values at the integers from $0$ through $3$ of:

f (x) = x^{2} - 4

Generate the table

Below each step is the screen you should see after pressing.

Next to each step is the screen you should see after pressing.

Step 1

Open the mode menu and choose Table. The setup screen opens directly. On a first visit, $f (x)$ and $g (x)$ are empty, $g (x)$ is marked optional, and Start, End, Step show $0$ , $0$ , $1$ .

Press:
Step 2

Enter $x^{2} - 4$ in $f (x)$ and press the equals key. This problem needs no $g (x)$ . A filled $g (x)$ would add a third column, so if it still holds an earlier function, type any key in its slot first, then press AC once: that clears only $g (x)$ . AC pressed before you type clears all five boxes. Press the equals key to move to Start.

Press:
Step 3

Set Start = 0, End = 3, Step = 1, pressing the equals key after each value. The final press generates four rows.

Press:

$f (x)$ , $g (x)$ , Start, End and Step are kept when you leave the mode or reload the page; the generated rows are not.

Read the table

Read each row across the $x$ and $f (x)$ columns:

$x$	$f (x) = x^{2} - 4$
$0$	$- 4$
$1$	$- 3$
$2$	$0$
$3$	$5$

The $x = 2$ row confirms $f (2) = 0$ , while the $x = 3$ row gives $f (3) = 5$ . Check the latter by substitution: $3^{2} - 4 = 5$ . The table shows only the selected inputs, not every value between its rows. To find an inequality's full solution intervals, use the inequality task instead of inferring them from this sample.

Compare two functions in one table

While setting up the table in step 2, after you enter $f (x) = x^{2} - 4$ and press , the selection moves to $g (x)$ . Type $2 x$ there and press to move to Start, then set Start = 0, End = 3, Step = 1 as before. The table now has three columns, with both function values on the same row for each $x$ .

$x$	$f (x) = x^{2} - 4$	$g (x) = 2 x$
$0$	$- 4$	$0$
$1$	$- 3$	$2$
$2$	$0$	$4$
$3$	$5$	$6$

To go back to two columns, clear $g (x)$ as step 2 describes, then press the equals key through Start, End and Step again.

The fx-991EX screen showing a function table for f(x) = x² − 4 with x from 0 to 3.

Build a function table on your fx-991EX calculator

Enter f(x) = x² − 4 once and see every value from x = 0 to 3 appear in one table.

Build the table More guides

Generate the table

Step 1

Step 2

Step 3

Read the table

Compare two functions in one table

Build a function table on your fx-991EX calculator