trigo graphs

Free Mobile Software To Draw Quadratic, Algebraic & Trigonometry Graphs

I was searching for some convenient learning tools for plotting of graphs when I came across this mobile software for plotting of graphs.

In one of my post on Drawing of Quadratic Graphs, I introduced a very popular free software Graphmatica.

I have tested out this mobile software on my hp. It works!

It is good for sketching cubic, quadratic and trigo graphs. Very simple to use by inputting the coefficients of each terms.

How to download from computer to your handphone.

Download the required file from here ( I downloaded the TVH-72g Graphing Calculator JAR )
When the file is on your desktop, bluetooth it to your handphone
Go to your handphone Received Files, click on it and it is available for use immediately!

See below for the screenshots:

screen-shot-mobile-graphs1

screen-shot-mobile-graphs2

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This software is beneficial for knowing the general shape of the graphs.

For more information, click here

I would love to hear your experience in using this cool mobile software. Leave me your comments in the section below.

O Level Additional Math - How To Prove Trigonometry Identity

Dear Ms Ong,

i had just taken my class test on simple trigonometric identities and well as further trignonometric identities yesterday.

sadly to say, i left all the proving of trigonometric identities blank which is worth a total of 9 marks.

Im starting to get panic about trigonometric identities for my coming common test,end of year exams as well as the big O Level.

so im actually here to ask you if you may guide me on how to do them in a faster way, because i realised ive no time to tackle those proving questions.

Best Wishes,
Priscilla Fong

I received this email among the many others in my mailbox. I think this is a common problem face in proving Trigo Identity question. I shall provide a few strategies to handle this sort of question.

Usually start with the left hand side or whichever side which is more complicated.
When given trigo functions in the form of sec, cosec or cot x , it is advisable to change it to basic trigo functions like sin, cos, tan
When question involves power (especially square power), formulas should be considered.
Have the END in mind before you begin i.e if the end result involves only sin, your working should eventually eliminate the other trigo functions and stick on to sin.
It should take less than 8 steps for a 3-4 marks proving question.
[pmath]a^2-b^2=(a+b)(a-b)[/pmath] is sometimes used in proving Trigo Identity. (Algebra rule)

I am going to use an example to illustrate how to use the above strategies

Q: Prove the identity [pmath](sec A - tan A)^2 = {1- sin A}/{1+ sin A}[/pmath]

[pmath](sec A - tan A)^2 =( {1}/{ cos A}-{sin A}/{cos A})^2[/pmath] (Change sec and tan into sin & cos)

= [pmath]( {1 - sin A}/{cos A})^2[/pmath]

= [pmath]{(1-sin A)^2}/{(cos A)^2} [/pmath]

= [pmath] {(1 - sin A)(1 - sin A)}/{(1 - sin^2 A)} [/pmath] (applying formula)

= [pmath] {(1 - sin A)(1 - sin A)}/{(1 - sin A)(1 + sin A)} [/pmath] (applying algebraic rule)

= [pmath]{1 - sin A}/{1 + sin A} [/pmath] (Proven)

Total number of steps = 6

Additional resource: You may want to read on A-Math Trigo Graphs here.

A-Math More Trigo Graphs

Another question for O Level Additional Mathematics (A-Math).

On the same diagram, sketch the graphs of

y=sin 3x & y=cos2x,
for x between 0 degree and 180 degree
Hence state the number of soutions to the equation
sin 3x=cos 2x
in the interval 0 degree less than or equals to x which is less then or equals to 180 degree

Click on image to have a larger view

Drawing of Trigo Graphs

Can you give an example of a drawing of tangent graphs? For eg, 3tan2x + 1, what does each stand for and how do i go about drawing?

From the drawing, you see only 1 diagram instead of a few diagrams as what most people will have.

The secret is............ I drew my x and y axis LAST which is the reason why my diagram is so neat and it takes me less than 2 min to complete : )

Click on diagram to have an larger view

A-Math Trigo Graphs

Terms you must understand in Additional Maths (A-Maths) Trigo Graphs

1. Amplitude
2. Period

You must be able to sketch given any trigo eqn and vice versa, i'e given graphs, find the unknowns. Just like this 2006 o level a-math p1 qn.

Note the common mistake to avoid!

If diagram appears too small for your @@s, click on the image and it will be enlarged.

Do it yourself first!

If diagram appears too small for your @@s, click on the image and it will be enlarged.