Today I’d like to post up some samples of common mistakes made by my students. I have compiled 5 examples here from their actual exam papers and made some notes in red about their mistakes.

I’ve also written the correct solution in red.

Drop me a comment or mail if you still have trouble understanding these examples.

Example 1

log 2 web

1) You cannot multiply 2 and 16 because the number 16 has power to it.

2) This student got the concept right which is to make the base number same on both sides.

Example 2

log 3 web

1) Here, the student made the mistake of adding Log 2 to the number 8. This makes it equals to 3 instead of 8 which is wrong.

2) What should be done is to leave the number 8, move the number 2 to RHS, and keep the log x on LHS

3) Observe my workings, in the 1st line, I multiplied 2 on both sides of equation to get rid of the fraction 2.

Example 3

log 4 web

1) Here’s a very very common mistake. Students often try to expand Log as if it’s an algebraic equation. It is NOT.

Example 4

yuva 1 web


thiv 1 web

1) Here are 2 answers by 2 different students on the Chapter Linear Law in Form 5 Add Maths. They are required to convert a non-linear equation to linear equation and very often, Log has to be used. So if your Log is terrible, then you’ll most likely struggle with this chapter.

2) Also note that this Chap – Linear Law is a very very very common question in Paper 2, Section B. Yes – you can choose not to do this, but let me assure you that this question is very easy to get 10 full marks, compared with Differentiation of Integration or Circles.

3) The top paper is wrong – the student made the same mistake as the one in example 3. They expanded the bracket as if it’s a normal Algebraic equation. In fact, in this paper, there are few other mistakes that I did not point out. See if you can spot them! :)

4) The paper in the bottom is by another student, and it’s correct.

Example 5

log 5 web

1) I’ve created a video to answer this type of indices question. View it here.

Feel free to drop me any questions that you need help with. What I suggest is you snap a pic of the question, or if you have a scanner, scan it in and mail me.

I will do the answers and post them up here. Or I may even make a video out of it :)