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### Re: O-Level Additional Math

Posted: **Wed Apr 20, 2016 10:04 am**

by **Boys2Men**

Hi there,

I need a private tutor, preferably a male with good experience and credentials to coach my son for A Math ( IP ) who is currently in Year 4.

Kindly pm me.

Thanks.

### Re: O-Level Additional Math

Posted: **Thu Apr 28, 2016 3:58 pm**

by **S-H**

Hi I can't find where to put this question, this is a sec 2 maths question, can someone kindly help me with this, thank you!

(a) Solve the following inequality:-

4x - 3

------- < 5x + 2

7

(b) Write down the smallest integer that satisfies this inequality

### Re: O-Level Additional Math

Posted: **Thu Apr 28, 2016 5:03 pm**

by **EconsPhDTutor**

S-H wrote:Hi I can't find where to put this question, this is a sec 2 maths question, can someone kindly help me with this, thank you!

(a) Solve the following inequality:-

4x - 3

------- < 5x + 2

7

(b) Write down the smallest integer that satisfies this inequality

(4x - 3) ÷ 7 < 5x + 2

⇔ 4x - 3 < 35x + 14

⇔ - 17 < 31x

⇔ - 17 ÷ 31 < x

The solution is x > -17/31.

The smallest integer that satisfies this inequality is 0.

Hope this helps and feel free to ask for any clarifications.

- Dr. Choo Yan Min

www.EconsPhDTutor.com
**If you found this answer helpful, then please help me out by spreading word of my services. I’m a new tutor in Singapore so I need some help getting word out! Thank you! **

### Re: O-Level Additional Math

Posted: **Thu Apr 28, 2016 6:24 pm**

by **S-H**

### Re: O-Level Additional Math

Posted: **Wed May 04, 2016 7:39 pm**

by **questionable_i**

Can anyone help me with this question?

Evaluate 2^x/2^4=2^1/2^(2y-2)

Thank you in advance. I need the answer ASAP.

### Re: O-Level Additional Math

Posted: **Wed May 04, 2016 10:36 pm**

by **kennethTutor**

questionable_i wrote:Can anyone help me with this question?

Evaluate 2^x/2^4=2^1/2^(2y-2)

Thank you in advance. I need the answer ASAP.

Applying a^m / a^n = a^(m - n),

2^x/2^4 = 2^1/2^(2y - 2)

2^(x - 4) = 2^(1 - (2y - 2))

2^(x - 4) = 2^(3 - 2y)

Comparing the indices on both sides,

x - 4 = 3 - 2y

x = 7 - 2y

I think this is probably a simultaneous equation question. You need another equation to solve for x and y.

### Re: O-Level Additional Math

Posted: **Thu May 19, 2016 8:45 am**

by **KSP2013777**

I need help with this question part (ii). Can somebody please help. Thank you

### Re: O-Level Additional Math

Posted: **Thu May 19, 2016 8:45 am**

by **KSP2013777**

I need help with this question part (ii). Can somebody please help. Thank you

### Re: O-Level Additional Math

Posted: **Thu May 19, 2016 3:04 pm**

by **kennethTutor**

KSP2013777 wrote:I need help with this question part (ii). Can somebody please help. Thank you

Use the double angle formula: cos 2β = 2 cos^2 β - 1

Make cos β the subject.

Because of the square root, there will be two possible answers (one positive and one negative).

Since 2β and α are in the same quadrant, and sin α is negative and tan 2β is positive, both angles are in the fourth quadrant (between 270° and 360°).

Angle β should be between 135° and 180° (2nd quadrant). Thus we expect cos β to be negative.

Ans should be -√(7/8)

### Re: O-Level Additional Math

Posted: **Sat May 21, 2016 2:37 pm**

by **KSP2013777**

Thank you, Kenneth Tutor.

Can you help me with another question, Please?

Thank you.