## O-Level Additional Math

- mathtuition88
- BlackBelt
**Posts:**895**Joined:**Thu Apr 25,**Total Likes:**16

- mathtuition88
- BlackBelt
**Posts:**895**Joined:**Thu Apr 25,**Total Likes:**16

### Expansion and Factorisation, HCI IP Sec 2 Revision Pack

Does your child need practice on

Practice Hwa Chong Institution

http://mathtuition88.wordpress.com/2013 ... orisation/

**Expansion and Factorisation**, especially the**more challenging questions**? It is a key technique that needs to be honed for the O Levels.Practice Hwa Chong Institution

**Expansion and Factorisation**(Sec 2, IP) here.http://mathtuition88.wordpress.com/2013 ... orisation/

- PiggyLalala
- KiasuGrandMaster
**Posts:**4053**Joined:**Tue May 24,**Total Likes:**23

### Re: Secondary School Mathematics

Need help to solve the following question.

Log (base 9) a = log (base 12) b =log (base 16) (a+b), find the value of a/b.

TIA

Log (base 9) a = log (base 12) b =log (base 16) (a+b), find the value of a/b.

TIA

- mathtuition88
- BlackBelt
**Posts:**895**Joined:**Thu Apr 25,**Total Likes:**16

### Re: Secondary School Mathematics

PiggyLalala wrote:Need help to solve the following question.

Log (base 9) a = log (base 12) b =log (base 16) (a+b), find the value of a/b.

TIA

Dear Sir/Mdm,

Please see my answer at http://mathtuition88.com/2013/05/12/o-l ... allenging/

Best wishes.

- PiggyLalala
- KiasuGrandMaster
**Posts:**4053**Joined:**Tue May 24,**Total Likes:**23

### Re: Secondary School Mathematics

mathtuition88 wrote:PiggyLalala wrote:Need help to solve the following question.

Log (base 9) a = log (base 12) b =log (base 16) (a+b), find the value of a/b.

TIA

Dear Sir/Mdm,

Please see my answer at http://mathtuition88.com/2013/05/12/o-l ... allenging/

Best wishes.

very much for the solution. Was using the wrong approach- change of base n made a big mess... haha..

I did not think of letting y = the log expression n change it into its exponential form.

Thank you so much.

- mathtuition88
- BlackBelt
**Posts:**895**Joined:**Thu Apr 25,**Total Likes:**16

### Re: Secondary School Mathematics

PiggyLalala wrote:mathtuition88 wrote:PiggyLalala wrote:Need help to solve the following question.

Log (base 9) a = log (base 12) b =log (base 16) (a+b), find the value of a/b.

TIA

Dear Sir/Mdm,

Please see my answer at http://mathtuition88.com/2013/05/12/o-l ... allenging/

Best wishes.

very much for the solution. Was using the wrong approach- change of base n made a big mess... haha..

I did not think of letting y = the log expression n change it into its exponential form.

Thank you so much.

You are welcome, glad to help.

That question is quite creative, enjoyed solving it.

### Re: Secondary School Mathematics

My son asks me a Math question from his MY Revision Paper which I need help. Find it rather challenging! Or if there is something not right? Could anyone out there kindly help to solve, thanks in advance.

" A father in his will left all his money to his children as such: $1000 and 1/10 of what then remains to the first born; then $2000 and 1/10 of what then remains to the second; then $3000 and 1/10 of what then remains to the third born; and so no. When this was done each child had the same amount. How many children were there? "

" A father in his will left all his money to his children as such: $1000 and 1/10 of what then remains to the first born; then $2000 and 1/10 of what then remains to the second; then $3000 and 1/10 of what then remains to the third born; and so no. When this was done each child had the same amount. How many children were there? "

### Re: Secondary School Mathematics

Qwertymum wrote:My son asks me a Math question from his MY Revision Paper which I need help. Find it rather challenging! Or if there is something not right? Could anyone out there kindly help to solve, thanks in advance.

" A father in his will left all his money to his children as such: $1000 and 1/10 of what then remains to the first born; then $2000 and 1/10 of what then remains to the second; then $3000 and 1/10 of what then remains to the third born; and so no. When this was done each child had the same amount. How many children were there? "

Father's money [-1000-][1U][-------------------9U-------------------]

Father's money [-1000-][1U][--2000--][1P][-----------9P-----------]

Father's money = 1000 + 10U

the money that 1st child will receive = 1000 + 1U

the money that 2nd child will receive = 2000 + 1P

Each child will receive the same amount of money

1000 + 1U = 2000 + 1P

1U = 1000 + 1P ------------(1)

9U = 2000 + 10P ----------(2)

(1)*9 , 9U = 9000 + 9P ---(3)

(2) = (3) ,

2000 + 10P = 9000 + 9P

1P = 7000

From (1)

1U = 1000 + 1P = 1000 + 7000 = 8000

Father's money = 1000 + 10U = 1000 + 10*8 = 81000

the amount of money that each child will receive = 1000 + 1U = 9000

No of children = 81000 / 9000 =

**9**

### Re: Secondary School Mathematics

jieheng wrote:Qwertymum wrote:My son asks me a Math question from his MY Revision Paper which I need help. Find it rather challenging! Or if there is something not right? Could anyone out there kindly help to solve, thanks in advance.

" A father in his will left all his money to his children as such: $1000 and 1/10 of what then remains to the first born; then $2000 and 1/10 of what then remains to the second; then $3000 and 1/10 of what then remains to the third born; and so no. When this was done each child had the same amount. How many children were there? "

Father's money [-1000-][1U][-------------------9U-------------------]

Father's money [-1000-][1U][--2000--][1P][-----------9P-----------]

Father's money = 1000 + 10U

the money that 1st child will receive = 1000 + 1U

the money that 2nd child will receive = 2000 + 1P

Each child will receive the same amount of money

1000 + 1U = 2000 + 1P

1U = 1000 + 1P ------------(1)

9U = 2000 + 10P ----------(2)

(1)*9 , 9U = 9000 + 9P ---(3)

(2) = (3) ,

2000 + 10P = 9000 + 9P

1P = 7000

From (1)

1U = 1000 + 1P = 1000 + 7000 = 8000

Father's money = 1000 + 10U = 1000 + 10*8 = 81000

the amount of money that each child will receive = 1000 + 1U = 9000

No of children = 81000 / 9000 =9

Wow! That's fast. Thanks a lot.

- alwaysLovely
- YellowBelt
**Posts:**19**Joined:**Wed Jan 14,

### Re: Cubic Equations

Solving cubic equations is taught in Secondary 3 Additional Maths.

There are three methods:

1) Synthetic division

2) Comparing coefficients

3) Long division

I've two videos on demonstrating how to solve a cubic equation using the first two methods.

I believe this post will be useful for you.

http://www.singaporeolevelmaths.com/201 ... nts-video/

Cheers!

There are three methods:

1) Synthetic division

2) Comparing coefficients

3) Long division

I've two videos on demonstrating how to solve a cubic equation using the first two methods.

I believe this post will be useful for you.

http://www.singaporeolevelmaths.com/201 ... nts-video/

Cheers!