E-Math Note : Usage of bracket in Expansion

Another TIP for students taking Elementary Mathematics (E-Math)

Qn: Expand and Simplify the following:


Method 1 : Expansion using one of the Algebraic rules


Did you see what is not right?

Method 2: Recognizing (A)^2 - (B)^2=(A+B)(A-B)

so (y+z)^2-(y-z)^2=(y+z+y-z)(y+z-[y-z])

Method 1:


Bracket is missing! the negative sign belongs to the expansion of (y-z)^2 not just y

Correct Ans:


Related Post

A-Math: Spot the Mistake in this Logarithm Equations I gave my Secondary 4 students 1 revision question per week. The recent one I marked was on the topic of Logarithms (the fresh-killer topic for many S...
A-Math: Quadratic Equation & Discriminant (Plus Common Mistakes & Counter Measures) Commonly asked in school and 'O' Level Examinations, many students also commit to commonly made mistakes. Watch the video (5 minutes) and see how you ...
E-Maths Note : Algebraic Expansion This is a topic some of which is learnt ever since Primary 6. Through my years of coaching, I notice quite a handful of students form blocks when t...
Binomial Expansion Teaches how to choose the RIGHT partner (: I always like to share with my students what each Math topic has to do with their everyday life, particularly their future. Yesterday, I did Binomi...
Top 7 Commonly Made Mistakes in Logarithm How many of you would like to learn Math faster? And how many of you would like to score more marks for Math? Do you know that one of the fastest ...

Hi, I'm Ai Ling Ong. I enjoy coaching students who have challenges with understanding and scoring in 'O' Level A-Maths and E-Maths. I develop Math strategies, sometimes ridiculous ideas to help students in understanding abstract concepts the fast and memorable way. I write this blog to share with you the stuff I teach in my class, the common mistakes my students made, the 'way' to think, analyze... If you have found this blog post useful, please share it with your friends. I will really appreciate it! :)

Leave a reply