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Tag Archives: secondary 3

Sec 3 Geometrical properties of circle ( Question solved ) See Video

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Recieved this question from one of my secondary 3 girl.

I videotaped the solutions so that my other secondary 3 students can see it.

–> Side note to JasC, you shall practice all the 60 plus questions possible untill you “kill” this topic. 😉

I thought you can skip the first video on the first part which you managed to solve. 🙂

 

Bye Bye!

Finally, time to chill out with my hubby! 😀

 

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Modulus function “MUST KNOWS” and questions for my O Levels AMaths students!!

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This is done especially for my O Levels (Secondary 3 and 4)  A Maths girls.

One of my student (Jasmine, yes its you!) showed me one good question on modulus function and got me thinking.

Decided to do up some basic “MUST KNOW” points for this topic and some questions for practice to ensure you folks got the technique for solving modulus function problems. 🙂

 

Modulus function MUST KNOWS

i.             |a| = |−a|

SO |a−b| = |b−a| (we need to form common factors to be brought out)

 

ii.             |a| ≥ 0

( Obviously right? Hee. You must get it before talking about other techiques to solve modulus functions)

SO |a| = a if a ≥ 0

But then this property is important in removing the modulus sign which is our objective when solving modulus functions questions.

 

e.g. |5 − 3| + |3 − 5| = 5 − 3 + |5 − 3| = 2(5) – 2(3)

 

iii.             |ab| = |a||b|

Always remember to keep the mod sign when expanding

 

iv.             |a/b| = |a|/|b|

Look out to form common factors too.

 

v.             |a|2 = a2

We can remove the mod sign by ‘squaring both sides’.

But the mod sign stays for odd powers

|a|3 ≠ a3!

 

Please complete these questions and hand up to me next lesson! 😀

Modulus function Questions

1)      | 3x-5 | + 2 |10-6x| = 25

2)      |21x + 28||3x-4| = 28

3)      |9a2 +24a+16| = 9

4)      5x = | x2 +6|

5)      | -4x2/5-x| = |10-2x/8 |

6)      |√ 3 x | = |-2x-3/ √3  |

7)      |x + √5||x − √5| = −6x

 

Have a great weekend!! 🙂