Graphing Calculator Tips

for TI-85

The calculator you use must have four built-in capabilities:

Graph a function

(1) Press <GRAPH>

(2) Press <F 1> to enter function for y(x)=

(3) After entering function, press <EXIT>

(4) Press <F 3> to Zoom

(a) Press <F 4> for Zoom Standard (10x10) or

(b) Press <More> then <F 3> for Zoom Trig

(5) Press <EXIT> then <F 5> for graph.

(6) Press <F 4> for Trace, then use arrow keys to trace curve.

(7) Press <F 2> for Range to set up your own domain and range.

(8) Press <MORE> twice then press <F 1> to Evaluate the function at a particular x.

Solve an Equation

(1) Press <2^nd> <SOLVER>

(2) After the Eqn: You should enter your equation – you must press <ALPHA>

<STO> for the = sign.

(3) Press <ENTER> to get the Interactive Solver Editor

(4) Make a guess for x =

(5) You may change the bounds (the default bounds are {-1E99, 1E99}).

(6) Press <F 5> to solve equation.

(7) Repeat with different bounds to solve for other roots.

Use this in connection with the Graph capability to see where other roots may be.

Calculate a Numerical Derivative

(1) Press <2^nd> <CALC>

(2) Press <F 3> for the first derivative.

(3) After der1( is displayed,

enter your function,

then a comma,

then the variable x,

then a comma,

then the value at which you wish to take the derivative,

then a right parenthesis.

(4) Then Press <ENTER> to get the numerical value of the derivative.

Calculate a Definite Integral

(1) Press <2^nd> <CALC>

(2) Press <F 5> for the integral.

(3) After fnInt( is displayed,

enter your function,

then a comma,

then the variable x,

then a comma,

then the lower bounds of the integral,

then a comma,

then the upper bounds of the integral,

then a right parenthesis.

(4) Then Press <ENTER> to get the numerical value of the integral.