• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Mathematics: Post your doubts here!

Messages
681
Reaction score
438
Points
73
T
Thank you very much for the effort, I appreciate it and will pray for you.

I just realised I had copied the question wrong(taken the x^3 as x^2). lol.

You're welcome :)

Haha I hate when that happens :p
 
Messages
869
Reaction score
374
Points
73
what is the gradient of the curve when it is parallel to the x-axis and also what is the gradient of the curve when it is parallel to the y-axis ?
 
Messages
681
Reaction score
438
Points
73
what is the gradient of the curve when it is parallel to the x-axis and also what is the gradient of the curve when it is parallel to the y-axis ?

Parallel to the x-axis is 0.
Parallel to the y-axis is 1/0.

If you ever forget or get confused, take any two points on the axis you want, and find it's gradient. :)
 
Messages
681
Reaction score
438
Points
73
what is the gradient of the curve when it is parallel to the x-axis and also what is the gradient of the curve when it is parallel to the y-axis ?

Hold on.. you mean the tangent to the curve is parallel to the x- or y-axis, right ?
 
Messages
681
Reaction score
438
Points
73
yeah what u said is right because now the question makes sense..thank u!!

You're welcome. Actually i got confused cuz you said the curve is parallel to the x-axis, which isn't possible. So you probably were talking about the tangent :)
 
Messages
869
Reaction score
374
Points
73
You're welcome. Actually i got confused cuz you said the curve is parallel to the x-axis, which isn't possible. So you probably were talking about the tangent :)
oh yeah sorry my bad i meant tangent :$
 
Messages
681
Reaction score
1,731
Points
153

Attachments

  • Capture.PNG
    Capture.PNG
    5.1 KB · Views: 11
Messages
345
Reaction score
394
Points
63
This is not technically a permutation question since it won't require the P...

5000 and 6000 .. meaning it's a four digit number which starts with a 5.

so first number is 5.. that's a given.

5 _ _ _

Now since repetition is allowed..

the next 3 numbers can be anything from 1,2,3,4,5,6

meaning it can be 5555 5432 or 5646 .. all are possible.

so 6 choices for all the 3 other spaces..

meaning it becomes

1 * 6 * 6 * 6... = 1*6^3
a bit absurd question it is, but why do u multiply a '1' in there?!
Jazak Allah khair ! :D
 
Messages
345
Reaction score
394
Points
63
http://www.examsolutions.net/maths-revision/syllabuses/CIE/period-1/specification.php
This is an amazing and hell useful website! (guaranteed) So, if anyone of u need help with understanding or anything!! this is it. I assure u. I only used this website to prepare for my AS math...and past papers of course...nothing else...no books! some topics arent covered yet thou. but use whatever u can!! Best of luck!
Jazak Allah khair! Cheers!
 
Messages
345
Reaction score
394
Points
63
nevermind anymore about question 2..i only need question 6 the diff equation
xdy/dx=1-y^2
rearrange so that all the x terms are at one side and y terms at the other.
so.... 1/(1-y^2) dy = 1/x dx
Now integrate both the sides,
$-sign for integration
$ 1/(1-y^2) dy = $1/x dx
P.S (1-y^2) is in the form a^2 - b^2 which is nothing but (a+b)(a-b)(remember??!)
so in order to integrate expressions like $1/a^2 - b^2 = [ 1/2a* ln(a+b/a-b)] (memorise this)
Therefore,
continuing with the integration,
$ 1/(1-y^2) dy = $1/x dx
[1/2*1 * ln(1+y/1-y)] = lnx +K where K is the common constant! :D
You're given: x=2, y=0
so put those in the eqn:
1/2 * ln (1+0/1-0) = ln2 +K
ln(1) is '0'.
therefore, K+ln2 = 0
K= -ln2 :DD
Now get the eqn
1/2 * ln(1+y/1-y) =lnx -ln2
1/2 * ln(1+y/1-y) -lnx + ln2 = 0

There u gooo!!
I hope u got it!! it can be easy...if u didnt understand then refer to the website i posted! u'll get it forever stuck in ur mind!!

Cheers!
 
Messages
1,824
Reaction score
949
Points
123
a bit absurd question it is, but why do u multiply a '1' in there?!
Jazak Allah khair ! :D

Well just to make it a bit clearer..

We have 5 to choose from one five... so it will be 1C1 which is 1 for first number.. then we can choose any one number from the 6 numbers.. for each of the next three numbers (1,2,3,4,5,6) since repetition is allowed...



1C1*6C1*6C1*6C1 = 1*6*6*6 = Answer
 
Messages
869
Reaction score
374
Points
73
xdy/dx=1-y^2
rearrange so that all the x terms are at one side and y terms at the other.
so.... 1/(1-y^2) dy = 1/x dx
Now integrate both the sides,
$-sign for integration
$ 1/(1-y^2) dy = $1/x dx
P.S (1-y^2) is in the form a^2 - b^2 which is nothing but (a+b)(a-b)(remember??!)
so in order to integrate expressions like $1/a^2 - b^2 = [ 1/2a* ln(a+b/a-b)] (memorise this)
Therefore,
continuing with the integration,
$ 1/(1-y^2) dy = $1/x dx
[1/2*1 * ln(1+y/1-y)] = lnx +K where K is the common constant! :D
You're given: x=2, y=0
so put those in the eqn:
1/2 * ln (1+0/1-0) = ln2 +K
ln(1) is '0'.
therefore, K+ln2 = 0
K= -ln2 :DD
Now get the eqn
1/2 * ln(1+y/1-y) =lnx -ln2
1/2 * ln(1+y/1-y) -lnx + ln2 = 0

There u gooo!!
I hope u got it!! it can be easy...if u didnt understand then refer to the website i posted! u'll get it forever stuck in ur mind!!

Cheers!
the key to the 8 marks is all in this point "P.S (1-y^2) is in the form a^2 - b^2 which is nothing but (a+b)(a-b)(remember??!)" -_- thanksss i got it now !!
 
Messages
345
Reaction score
394
Points
63
the key to the 8 marks is all in this point "P.S (1-y^2) is in the form a^2 - b^2 which is nothing but (a+b)(a-b)(remember??!)" -_- thanksss i got it now !!
hahaah...u know that integration technique/point, i found it in some other book....it wasnt there in mine or maybe i did not check...hahah but learn that...i came across a similar question in o/n 2008... this was still simple!! :D
 
Messages
12
Reaction score
4
Points
13
I am having problem in 9709/62/O/N/09 q7 ii why are we adding the previous probablity it should be subtracted :/ can anyone help please
 
Messages
124
Reaction score
30
Points
28
thaank u so much specially permutation , i had great ambiguity here
 

Attachments

  • 922728_370939636360498_1567664426_n.png
    922728_370939636360498_1567664426_n.png
    34.3 KB · Views: 5
Top