Maths, Addmaths and Statistics: Post your doubts here!

[robinhoodmustafa]

Without using a calculator evaluate
(lg 5)^2+lg2 lg50

2(lg5) + lg5 lg20

2lg 10 + lg100
lg100 + lg100

After that I dont know.

 

[PhyZac]

Without using a calculator evaluate
(lg 5)^2+lg2 lg50

(lg 5)^2 + lg2 lg 50
(lg 5)^2 + lg2 lg(2 * 25)
(lg 5)^2 + lg2 (lg 2 + lg25)
(lg 5)^2 + lg2 (lg 2 + lg 5^2)
(lg 5)^2 + lg 2 ( lg 2 + 2log 5)
(lg 5)^2 + lg2*log2 + 2*log2*log5
(lg 5)^2 +2*lg2*lg5 + (log2)^2 [Now you can notice the form a^2 + 2ab + b^2 = (a+b)^2
[lg5 +lg2]^2
(lg(5*2))^2
(lg10)^2
1^2
1

 

[Hamza0909]

Anyone can post the Nov 2012 Maths paper for O levels please....? secondly, make x the subject of formula.. x(x-2)=t-2
Thanks.

 

[flora16]

hey! i want some help...
i need past papers/links from before 2000 along with there er and ms
plz help!
thnx.

 

[tdk]

Thnx a lot. I have a doubt here:
If a measurement is reported as 7 mm rounded to nearest mm, then its lower limit is obviously 6.50 mm but what is its upper limit? Is it 7.49 or 7.50?

 

[tdk]

hey! i want some help...
i need past papers/links from before 2000 along with there er and ms
plz help!
thnx.

Do u need 4024(Syllabus D) or 4037(Add Math)?

 

[PhyZac]

Thnx a lot. I have a doubt here:
If a measurement is reported as 7 mm rounded to nearest mm, then its lower limit is obviously 6.50 mm but what is its upper limit? Is it 7.49 or 7.50?

Asslamu Alikum Wa Rahmatullah Wa Barakatoho

7.5
because the actual lower limit is 7.499999999999....so when you round you get 7.5
But it is usually written in the form
7.5>x>=6.5 ( read as: xis less than 7.5 and more than or equal to 6.5)

 

[Suchal Riaz]

Anyone can post the Nov 2012 Maths paper for O levels please....? secondly, make x the subject of formula.. x(x-2)=t-2
Thanks.

http://www.mediafire.com/?az21dvjfvqga1 all winter 2012 papers

 

[Suchal Riaz]

Thnx a lot. I have a doubt here:
If a measurement is reported as 7 mm rounded to nearest mm, then its lower limit is obviously 6.50 mm but what is its upper limit? Is it 7.49 or 7.50?

let me tell u an easy method. they say nearest to 'a' millimeter. mean 1 millimeter. divide 1 by 2. u get 0.5 millimeter. add it to the real value u get upper bound and subtract it u get lower bound.
for example is they say 1245m to the nearest 5 m. divide by 2 u get 2.5 add it u get 1247.5 cm as upper bound. subtract u get 1242.5 as lower bound.
if u have gud concept of it u can just do it by looking at it but sometimes u have confusion so use this method rather than guess.

 

[Suchal Riaz]

Anyone can post the Nov 2012 Maths paper for O levels please....? secondly, make x the subject of formula.. x(x-2)=t-2
Thanks.

 

[aiman farooq]

thanku...

 

[Haris Bin Zahid]

Please I need full explanation of this relative velocity question:
A coastguard station receives a distress call from a ship which is travelling at 15 km/h on a bearing of 150°. A lifeboat leaves the coastguard station at 15 00 hours; at this time the ship is at a distance of 30 km on a bearing of 270°. The lifeboat travels in a straight line at constant speed and reaches the ship at 15 40 hours.
(i) Find the speed of the lifeboat.
(ii) Find the bearing on which the lifeboat travelled.

PhyZac , scouserlfc , FAHMEED

 

[PhyZac]

Please I need full explanation of this relative velocity question:
A coastguard station receives a distress call from a ship which is travelling at 15 km/h on a bearing of 150°. A lifeboat leaves the coastguard station at 15 00 hours; at this time the ship is at a distance of 30 km on a bearing of 270°. The lifeboat travels in a straight line at constant speed and reaches the ship at 15 40 hours.
(i) Find the speed of the lifeboat.
(ii) Find the bearing on which the lifeboat travelled.

PhyZac , scouserlfc , FAHMEED

Assalamu Alikum
What are the answers?

Is the speed 60 km/h and bearing 310?

 

[Haris Bin Zahid]

Assalamu Alikum
What are the answers?

Is the speed 60 km/h and bearing 310?

Thanks a lot for sparing your precious time to answer my question.
But I'm afraid, the speed is 39.7 km/h and bearing is 251.

 

[Suchal Riaz]

pardon me if i made any silly mistake but i hope u get the concept.

 

[Suchal Riaz]

Thanks a lot for sparing your precious time to answer my question.
But I'm afraid, the speed is 39.7 km/h and bearing is 251.

.
sorry for wasting ur time by
i got my mistake. wait. here is correct solution wrong solution
but look at that solution as if the question was the other way around

 

[Zoya Shahab]

Given that lg 2=a and lg3=b and that lg x=3a-4b+1 find x.
Express lg cube root 972 in terms of a and b.

 

[examkiller]

Solving inequality y+2x=1 or y+2x>1 .
please help how to plot the points and finding x and y.

 

[Suchal Riaz]

Given that lg 2=a and lg3=b and that lg x=3a-4b+1 find x.
Express lg cube root 972 in terms of a and b.

 

[Zoya Shahab]

View attachment 21948

View attachment 21947

I cant understand Where did the 18 came from???. And by the way it's cube root not square root!!