Chapter 8: Draw Instructions
126
Drawing Tangent Lines
Drawing a Tangent Line Directly on a Graph
To draw a tangent line when a graph is displayed, follow these steps.
1. Select
5:Tangent(
from the
DRAW
menu.
2. Press
†
and
}
to move the cursor to the function for which you want to draw the tangent line.
The current graph’s Y=
function is displayed in the top-left corner, if
ExprOn
is selected.
3. Press
~
and
|
or enter a number to select the point on the function at which you want to draw
the tangent line.
4. Press
Í
. In
Func
mode, the X value at which the tangent line was drawn is displayed on
the bottom of the screen, along with the equation of the tangent line. In all other modes, the
dy/dx
value is displayed.
5. Change the fixed decimal setting on the mode screen if you want to see fewer digits displayed
for X and the equation for Y.
Drawing a Tangent Line from the Home Screen or a Program
Tangent(
(tangent line) draws a line tangent to
expression
in terms of X, such as Y1 or X
2
, at point
X=
value
.
X can be an expression.
expression
is interpreted as being in Func mode.
