Let's recap on these graphs.

Starter : (10 mins)
A) Trigonometrical Graphs :
Hope you still remember your trigonometrical graphs.
y = sin x

y= cos x


y = tan x

Explore on this geogebra applet : http://www.geogebra.org/en/upload/files/couture_daniel/TrigFunctions.html


Based on the general form of :
y = asin(bx+c) + d
y = acos(bx+c) + d
y = atan(bx+c) + d

Task 1:
Comment on the effects of a, b, c and d on the various trigonometrical graphs.
Click on this link and input your findings. http://linoit.com/users/angcc/canvases/3V2%20Trigo%20Graphs

Main Course : (30 mins)

Look at the picture below , is it awesome?

These are some important notes for your readings.

Reading 1: Shading with Style


Reading 2: Storing and recalling picture/s

Storing the picture

In order to keep once made plot for future use (next measurement result will replace the plot with the new data) we will use the Storing the picture mechanism. You can save the whole picture

(but not the data that produced it) in a Picture variable.

Do this:

Choose STO from the DRAW menu and then 1: StorePic You will be prompted for the name of the variable. System allows only special picture variable names which you can find under the VARS 4:Picture menu as Pic1; Pic2 etc.

Point Pic1 and press ENTER

Since then your picture is saved and you can retrieve it at any time in the future. In this way you can store up to 10 pictures.

Storing the function scenarios

The established expression for Y1 together with the Window settings and all Mode settings forms a set of information that defines the function and its graph. This set can be stored as Graphic Data Base

GDB single variable and retrieved later providing all settings back (except constant values that might be updated in the meantime).

This saves a lot of time that usually is spent on constructing the function expressions and redefining the Window.

To store settings as a GDB do this:

Choose the 3:StoreGDB option from the DRAW STO menu. You will be prompted for the name of the variable. Graphic data base has to be stored under one of the 10 available variable names which you can find in the VARS 3:GDB list. Complete the procedure with ENTER.

Now you can change the function Mode

Let's have fun here. Can you identify the various trigonometrical graphs for each of the pictures?

Picture 1
Picture 2
Picture 3
Picture 4
Task 2:
Click on this link to input your guess for each group. http://linoit.com/users/angcc/canvases/3V2%20Trigo%20Graphs

Do you wish to create one of such design too.? Let's start our adventure here.


Task 3:
With these new graphing skills mastered, you will work in your group to create a picture (Happy Birthday Singapore 2011) using all the trigonometrical functions (Sine Function, Cosine Function and Tangent Function). You may wish to consider the four pictures above and look at how you can enhance them. It will be better if you have your group creation. You are to submit a neat, completed diagram and a completed table as illustrated below.
Upload your completed work into this link.



Dessert: (10 mins)

With these knowledge on graphing, can you help to solve this problem.

A Ferris wheel of diameter 40m and whose centre is 25m above the ground. The wheel takes 6 minutes (360 seconds) to make one complete revolution. Peter is currently at point A, which is 25 m above the ground.


a) Sketch a graph of y(m), the height of Peter's position from the ground, against time t (seconds) through one revolution. Write down the equation of y in terms of t. Complete this table below.






Using Excel, create a scatter plot of the set of data above.What do you notice? What is the equation of y in terms of t?

Option 1: Create the Excel applet yourself.
View this video if you have no knowledge to create a scatter plot for a set of data.

Option 2: Using this applet, input the respective values into the yellow and red cells. [password :trigo]

b) When would Peter be 40 m above the ground?

Click here to submit your solution.




All the work must be completed by latest 3pm on Friday 19th August 2011. I will be locking this page after 3pm.

Reminder : You must complet your textbook Exercise 11.3 (Trigo. Grpahs ) by 23rd August . Sumbit to me in hardcopy
Exercise 11.3 : Q 3a, Q3b, Q3e, Q3h, Q7