User Manual

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.