TI-84 Graphing Calculator

1. Basic Computations2. Graphing Navigation3. Graphing Tools4. Statistics and Algebraic

Models

First…

Clear Memory2nd, MEM, Reset: all RAM, ENTER

Degree Mode MODE, Degree,

ENTER,2nd, QUIT

Basic Computations

– Example:

– Answer: -34.12716165

– Looks Like:

2 9 6

4 1

3 63

4

8

e

(( ( ) ) / ( ( ) )) (( ( ) ) / ( ^ ))2 9 6 4 1 4 3 6 83 x e

Graphing Navigation…

Typing Equations

– Always set your equation equal to zero

– Use the correct syntax (see Basic Computations)

– Turn off Plots2nd, STAT PLOT, 4:Plots Off, ENTER

Graphing Navigation…Viewing Window

To display x:[-10, 10]; y:[-10, 10]* ZOOM 6: Standard

To show all points on a scatter plot* ZOOM 9: Stat

To show entire graph on the screen * ZOOM 0: Fit

To zoom in/out from the center of the screen* ZOOM 2: Zoom In* ZOOM 3: Zoom Out

* Best option…learn to use the WINDOW to manually edit the length of the x-axis and y-axis

Graphing Navigation…Viewing Window

Example: * Graph x3 – 1.1x2 – 65.4x = – 229.5

x:[4.95, 5.15]; 0.05y:[–0.1, 0.1]; 0.01

Does the graph have any zeros?

Graphing Tools…

Calculating Extrema (minimum/maximum)2nd, CALC3:minimum or 4: maximumLB, ENTER, RB, ENTER, Guess?, ENTERx = (where it occurs)y = min/max value

Graphing Tools…Finding Zeros/Roots (x-intercepts,

solutions)2nd, CALC2: zeroLB, ENTER, RB, ENTER, Guess?, ENTERx = (where it occurs)y = 0

Graphing ToolsLocating Points of Intersection (two

graphs)2nd, CALC5: intersect1st curve, ENTER, 2nd curve, ENTER, Guess?,

ENTER

Practice:* Find the zeros, maximum, and minimums:

x4 – 7x2 + 6x* zeros: –3, 0, 1, 2 * max: (0.456,

1.323)* min: (–2.056, –24.057)* min: (1.601, –1.766)

x3 – 4x2 – 7x + 10* zeros: –2, 1, 5 * max: (–0.694, 12.597)

* min: (3.361, –20.745)

10x3 + 7.5x2 – 54.85x + 37.95* zeros: -3, 1.1, 1.15 * max: (–1.625, 103.976)

* min: (1.125, –0.026)

Statistics and Algebraic Models…

Scatter Plots

* Plotting Points•Clear Y=•Turn on Plot 1: 2nd, STAT PLOT, 1, ON, ENTER

•Enter ordered pairs: STAT – 1:Edit– Enter x-coordinates for L1– Enter y-coordinates for L2

– ZoomStat to view graph

Statistics and Algebraic Models

Lines of Best FitSTAT – CALC– Choose type of equation:

4: Line5: Quadratic6: Cubic7: Quartic

Type L1, L2, Y1

-Use the 2nd button to type L1 and L2-Don’t forget the comma-To find Y1 press VARS, Y-VARS, 1:Function,

1: Y1

Press ENTER

The algebraic model is shown on the graph, and the equation is located in Y1

Example:

* Make a scatter plot of the data:

* Find a linear model, quadratic model, cubic model

Linear Equation: y = 0.572x + 5.24 Quadratic Equation: y = 0.059x2 – 0.617x + 8.211Cubic Equation:

y = –0.0124x3 + 0.4334x2 – 3.269x + 10.0814

x 0 5 10 15 20

y 10.1 2.8 8.1 16.0 17.8

Make a 2 scatter plots of the data:

* Men: Plot 1

* Women: Plot 2

* set x = 0 to represent the year 1970

* Find a quadratic model and cubic model for the data

* Which model best fits the data?* What is the life expectancy for men & women in 2020?

Life Expectancy (years)

Year of Birth Men Women

1970 67.1 74.7

1980 70.0 77.4

1990 71.8 78.8

2000 73.2 80.2

2010 74.5 81.3

Find the minimum, maximum, and zeros of each function.

Then find the point(s) of intersection of the functions.

The table shows U.S. energy production for a number of years.

a. Find a linear model, a quadratic model, a cubic model, and a quartic model for the data. Let x = 0 represent 1960.

b. Graph each model. Which one is the better fit?

c. Use each model to determine the current energy production.

Which model has the most reasonable answer?