Using Graphmatica

							Using Graphmatica
                                 Graphmatica is a program for drawing all types of graphs. You
                                 place a rule in the address bar and a graph is drawn. The rule
                                 must be written using x and y variables.

                                 Before using Graphmatica you need to know how to change a
                                 few things.

                                     1. Go to Labels  legends and
                                        make the increments for both x
                                        and y =1

                                  2. Then go to View Colours and make the background white

                                  3. Then go to ViewGrid range
                                     and make the range as shown

                                  4. To clear graphs click Clear




Beginning Investigations
Investigation 1: Linear rules y = mx + c form. How does the value of m effect the graph?
On the one grid get Graphmatica to draw the following graphs.

A. y = x      B. y = 2x      C. y = 3x      D. y = 0.5x    E. y = 2/3x    F. y = -x       G. y = -2x

Complete: In the general linear form y = mx + c , m represents R…. of C……             for a particular
rule. On the graph the value of m changes the G………..        or S……..


Investigation 2: Linear rules y = mx + c from How does the value of c effect the graph
On one graph grid get Graphmatica to draw the following graphs

A. y = x      B. y = x + 1   C. y = x + 2   D. y = x +3 .5 E. y = x - 2   F. y = x - 5

Complete: In the general form y = mx + c The value of c determines the V…………I……….
whose coordinates are ( .. , .. )


Investigation 3: Linear rules Special types
On one grid get Graphmatica to draw the following graphs

A. y = 1             B. y = 5               C. y = -4      D. x = 3               E. x = -2

Complete. All equations of the form y = c produce H…………….Line graphs. All equations of the
form x = b will produce V………..Line graphs




Source: henchel.graeme.e@edumail.vic.gov.au                                               6/06/2008
Advanced Investigations

Set the grid range as shown



Investigation 4: Gradients, Intercepts and Restricted domains
On one grid enter the following rules with the extra stuff in the curly braces. Observe the effect
of adding the information in the curly braces.

A. y = x + 3 {-5, 2}   B. y = 4 {0, 6}      C. y = -5/4x + 5 {0, 4}

Task 1: Determine the rules that will produce the
following graphs




                                                               Hint: To clear the grid lines go to
                                                               View Colours and make the
                                                               gridlines white.

                                                               One of your rules will be

                                                               y = -7/3x + 7 {0, 3}

                                                               Use the grid range below




Source: henchel.graeme.e@edumail.vic.gov.au                                                6/06/2008
Investigation 5: Families of rules

Put in the following rule: y =a*x {a: 0, 5, 1} and see what happens.

Put in the rule y = 2x + a {a: 0, 6, 1} and observe what happens

Task 2: Try to determine the rules and construct the following families of graphs




Investigation 6: Graphs of inequalities

Put the following rules into graphmatica and see
what happens A. y < 2x + 3 B. y > x + 4

Task 3: Determine the rules and construct the
following diagram.

Hint: Two of the rules are written as inequalities
and one is specified as a family of lines

 Really Advanced Investigations:

 Put in the following Rules
 y > x^2 and y < 0.5x^2

 Put in the following rules
 (x-3)^2+(y-3)^2<4 and (x+2)^2+(y-2)^2<1

 Put in the following rule
 y < sin(x) and y > sin(2x) + 2

 Challenge:
 Create a smiley face using graphmatica

Source: henchel.graeme.e@edumail.vic.gov.au                                         6/06/2008