CAT | Video Learning

Feb/10

E-Math: How To Multiply Matrices (Video)

10 Comments | Posted by alwaysLovely in E-Math, Video Learning

This is my first attempt this year to produce a video. Should the response be good, I will use video to share more tips and strategies with my audience, so please leave me a comment.

Please pardon me the ‘echo’ effect in my introduction and also the low resolution. I was using my new logitech webcam :D

I’m working towards producing better quality videos. Share tips on this if you have any. Would appreciate it.

For more posts on matrix, please refer to the related posts below.

I look forward in hearing your comments and the answer to the question in the video.

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Mar/09

[Video] E-Math Popular Exam Question: Finding Ratio of Areas in Vectors (Includes 3 Strategies & Revision of Similar Triangles)

9 Comments | Posted by alwaysLovely in E-Math, Video Learning, Weekly Question

In this post, we are going to discuss on the applications of vectors - Finding Ratio of Areas. This is a popular section in examinations and based on my many years of experience, students simply don’t like it due to many of them disliking and not making sense of the topic on Similar Triangles.

Strategy #1 : Similar Triangles

In Similar Triangles, the ratio of 2 similar triangles can be easily found by squaring the ratio of their corresponding length.

$({A_1}/{A_2})=({l_1}/{l_2})^2$

Strategy #2 : Common Base/Common Height

I am going to use this examination question below to illustrate the application of Strategy #2. This strategy works when the triangles shared either a common base or a common height. And that the triangles are not similar.

Watch the video below to find out if your answers are correct. Included in this video is a trick which will help you to ’see’ your answer faster!

Rate the video or leave me a comment or question.

Strategy #3 : Overlap

When strategy 1 or 2 do not work and the question involves repeated triangles, overlap is the strategy you can apply. Overlap involves equalizing of ratio of THE triangle which overlaps.

ratio of areas in vectors, similar triangles, vectors Hide

Mar/09

[Video]E-Math: Basics of Vectors (Plus: Video Solution of an Exam Question)

1 Comment | Posted by alwaysLovely in E-Math, Reader Question, Video Learning

Vector is a nightmare for some students especially if you do not like Physics. But for O level Elementary Mathematics, the few concepts are still quite straightforward to grasp if you follow through step by step.

In this post, I am going to discuss the Basics of Vectors which include:

Finding magnitude of vectors
How to find vectors
Parallel vectors & its significance

This is the exam question used for illustration.

|Magnitude| of vectors

When vectors are given in column vector form: (matrix{2}{1}{x y}) , you can find the magnitude of the vectors usually by applying Pythagoras Theorem.

So magnitude of vectors = $sqrt{x^2+y^2}$ . If you do not wish to remember this, you can always draw a diagram in 5 seconds to be able to find the magnitude of any vectors. (This is shown in the video below)

How to find vectors

Finding vectors is just like deciding an alternate route for your journey. You would want to take note of the start point and the end point. For example, vec{AB} = vec{AO} + vec{OB} My starting point is A, transition point is O and the end point is B.

Hint: When diagram is given, refer to diagram for help to plan the ‘alternate’ route. Otherwise, consider the points given in the question.Sometimes, 3 or more vectors can be involved.

Parallel Vectors

We can tell that 2 vectors are // to each other when they are expressed in this relationship:

vec{AC} =k vec{BD} where k is a scalar factor.What this means is that vec{AC} is // to vec{BD} and the magnitude of vec{AC} is k times that of vec{BD}

We discuss about // vectors in parallelograms and trapeziums too!

Hint: Parallel vectors have same ‘gradient’.

This is the question which I use to illustrate the 3 points above:

How did you find vectors so far? Is it easy to understand or you do not seem to know anything? Leave me your comments. I would love to hear from you!

In the next post, I will be discussing Finding Ratio of Areas in Vectors & the Strategies Involved.

magnitude of vectors, parallel vectors, vectors Hide

Dec/08

Youtube helps students to do maths

0 Comments | Posted by alwaysLovely in Learning Tools, Video Learning, about singaporeolevelmaths

Youtube helps students do maths

I read with interest on this article (taken from Digital Life Singapore).

Nicole, the student mentioned that she can learn at her own pace anytime, anywhere. And if there are any concepts she wasn’t clear, she was able to rewind and replay till she understood what they were all about.

With the advancement of technology, learning can be so accessible and it’s all for free and most importantly, learning is only through medium which is likeable and popular with the students.

singaporeolevelmaths.com has been using videos for teaching tools as well and I am going to introduce more videos in 2009 as part of adding value to all our readers. So keep a lookout for these videos which will absolutely help you in your Mastery of your ‘O’ level Math. Here are some of the previous videos: