E-Maths

E-Math: Quadratic Checklist

checklist-em As I'm writing this post, we are only 89 days away from GCE 'O' Level Elementary Maths Paper 1.

Personally I think in this last phase of preparation, students must feel confident by reflecting on the things they've understand all these while.

I'm going to start this checklist for both E-Math & A-Math in this countdown towards 'O' Level 2010 and I hope you find it useful & beneficial in boosting your confidence and motivating yourself to do better.

For the topic of Quadratic, do you know

How to find the intercepts ( x & y), the turning point (minimum or maximum), given a quadratic graph?
How to sketch a quadratic graph given any type of quadratic equation?
How to complete square for a quadratic equation?
How to state the minimum or maximum from a completed square equation?
The various methods to solve a quadratic equation?
How to handle a problem solving question in Paper 2 involving quadratic concepts?

Above are the main concepts you need to know for Quadratic, feel free to add on any more in the comment section so that more readers can benefit from your sharing.

Study smart & stay cool!

E-Math: Adding & Subtracting Algebraic Fraction the Real Disguise Way (Video)

real-disguise With the completion of June Intensive Revision BootCamp over the school holidays, it has been my great pleasure to share with the participants on how to understand confusing Maths concepts easily, use a shorter time to solve their questions, enjoy learning :)

In the next few weeks, I'm going to share with you some of the important concepts I taught in my workshops. I hope you find the posts and videos useful. Remember to leave me a comment and subscribe to my blog (found on the top right hand side of this website).

Adding & Subtracting Algebraic Fraction is suitable for Secondary one to four students.

Length of video : 5 minutes.

Type of Numbers In A Simple Mindmap

Students whom I coach know that I'm a 'lazy' person when it comes to memorizing. So the way I teach is also free of memory work most of the time or if memorization is involved, I will cook up funny, ridiculous mnemonic (I can't spell this word, had to google for correct spelling) to help them remember better.

In this post, I'm sharing with you how I come out with a simple mindmap from Mindmeister.com to remember the type of numbers. For example, what are integers, whole numbers, natural numbers? I get confused easily and I'm sure some of you also face the same problem, isnt it?

Click on image for a bigger view.

This is useful in topics like Set Notation and Inequality, topics in E-Maths. If you like the mindmap, feel free to save it by 'Right Click' and 'Save as'. You can refer to it whenever and wherever.

If you're having problems understanding Set Notation, Inequality, join me at my Intensive Revision BootCamp this holidays. Click here for more information.

E-Math: How to Construct Angle and Perpendicular Bisector 'Live Demo'

I taught my E-Math class on 'How to Construct Angle and Perpendicular Bisector', a skill learnt in lower Secondary and forgotten by many Secondary fours.

You must know the steps. I'm so glad that when I found something really useful which shows the step-by-step. It's like a 'live demo'.

You must definitely check out this website on construction:

Angle Bisector: http://www.mathopenref.com/constbisectangle.html

Perpendicular Bisector: http://www.mathopenref.com/constbisectline.html

On top of these 2 skills, I suggest the following as well which could be tested together in a question.

Concepts of bearing
Angle properties of Circle
Construction of quadrilaterals
Special properties of quadrilateral eg Do you know the diagonals of a kite intersect at 90 degrees?

[Video]E-Math: Speed-time Graph to Distance-time & Acceleration-time Graph

reader-qn

I was asked the above question in this comment. I understand many students are facing the challenge in sketching distance-time graph given speed-time and vice versa. I have prepared 2 videos to share with you what I taught my students in my weekly coaching programme.

Video 1: Convert Speed-time graph to Distance-time graph.
(10 min)

Click here for the direct link.

Video 2: Convert Speed-time graph to Acceleration-time graph.(3min)

(I'm sorry there's an error in the video at time 2:10s, the acceleration should be -6)

Click here for the direct link.

How 16 Years Old Calculates Income Tax

During this period of time, a Singapore website is ranked high in the search engines. Do you know which website? With the deadline for filing tax to be on 15 April, many people are flocking to IRAS to do their last minute e-file.

IRAS-Yahoo

For a 15 - 16 years old teenager, he gets transformed into a tax officer (though a really entry level one) where he learns the basic in calculating the income tax.

Let's use the following question as an example,

Income-Tax

Chargeable income = Gross annual income (inclusive other income streams like rental etc) minus reliefs

Mr Tan income is only from his work, so gross annual income

= 3250 x 12 = 39 000

Total reliefts

=3000 + 2000 + 2000 x 2 + 7800 + 600 + 2/100 x 39 000

=18 180

Chargeable Income = 39 000 - 18 180 = 20 820

We can refer to the table of tax rate to calculate the amount of income tax Mr Tan has to pay.

Income-Tax

We choose the one circled in red:

First 20 000: $0

Next 820 (20 820 - 20 000): 3.5/100 x 820 = $28.70

I hope you find this post useful. Leave me your comment on Income Tax. Have you learnt the concept? Do you know it's under the topic of 'Everyday Math'?