Mathematics: Post your doubts here!

[Dug]

thanks buddy btw even i was doing it the same way but you see when i was solving it the answer was coming to 0.444 as i have a MS calculator and when i was checked now with ab/c i could see it means the same as 4/9 i guess i need to get myself an ES calculator now or get used to using the ab/c button more often anyways thanks man (despite you mentioned it but i should say this as you helped me freakout less and helped me figure out the problem and well sure i pray for your success best of luck

Btw aaakhtar19 deserves as much credit as I do. Thank him too

 

[Hazkeel Rizvi]

yeah dude wait

 

[Hazkeel Rizvi]

Please solve this question , i tried it doing so many times but i am unable to get the same gradient ( as per marking scheme ) and equation required to be shown in part (i)

thanks alot man eventually the solution helped me recognized the silly mistake of not using the ab/c button to find out that 0.444 is the same as 4/9

 

[Dug]

U just thanked yourself

 

[PearlPeriwinklexo]

wel i dont undrstnd wat u wanna ask here fr qstn 8 but it should be done this way have a look

the parameter of a rectangled plate is 2(x+y)
the parameter of circle is 2.pi.x

as it's one frth of the circle so (2.pi.x)/4 to get the parameter of the quadrant

now ad both of them and equate to 60

2(x+y) +(pi.x)/2 =60
2(x +y) + (pi.x)/2 = 60

( 4(x + y) + (pi.x))/2 = 60 send the 2 to R.H.s
4(x+y) + (pi.x) =120

4(x+y) = 120 - (pi.x) now send 4 at that side for divide

(x+y) = (120 - (pi.x)/4

x+y = 30 - pi.x/4

y = 30 -pi.x/4 -x Ans

THANK YOU SOOO MUCH!!! I understand now

 

[Esme]

Please explain the (i) part.
Here the mark scheme :

 

[Nikesh]

Please explain the (i) part.View attachment 8452
Here the mark scheme :View attachment 8453

U r given some values,
Total number of Females (Fn) = 12
Total number of ppl who watch "Kids andKops" (Kn) = 16
Number of female who watch "Kids and Kops" (In) = 3
now
P(Fn or Kn or both) = 12/30 +16/30 + 3/30 (Since 3/30 signifies for the intersection of female and who watch "KIDS and KOPS"
calculate and u will get your answer.....

 

[iHatesEssays]

Assalamoalaikum!

Good news for you all!! :Yahoo!:

Stuck somewhere in Maths?? Post your queries here and destined007 (others are also welcome! ) will answer it at the earliest, InshaAllah! 8)

P.S. I'm busy these days, so I can't promise to be there for help. I've done P1, M1, S1 so far and will be starting P3 in a couple of days, InshaAllah!

May Allah give us all success in this world as well as the HereAfter...Aameen!!

And oh yeah, let me put up some links for A level Maths Notes here.

Check this out! - Nice website, with video tutorials!

My P1 Notes! - Only few chapters available at the moment!

Maths Notes by destined007

Some Notes for P1 and P3 - shared by hamidali391

A LEVEL MATHS TOPIC WISE NOTES

MATHS A LEVEL LECTURES

compiled pastpapers p3 and p4 - by haseebriaz

Permutations and Combinations (my explanation)- P6

Permutations and Combinations - P6

Vectors - P3

Complex No. max/min IzI and arg(z) - P3

Sketcing Argand Diagrams - P3 (click to download..shared by ffaadyy)

Range of a function. - P1

Jazak Allah Khair!
mathy..

Is it possible to integrate y=x!
lol jks

 

[roadtrip9o9]

http://www.xtremepapers.com/papers/...AS Level/Mathematics (9709)/9709_w07_qp_1.pdf Question 11 .. part 2 3 4 and 5 wid da concepts plz :/

 

[Chooi1993]

Anyone know how to do q10 (ii)(b) ?
http://www.xtremepapers.com/CIE/International A And AS Level/9709 - Mathematics/9709_w10_qp_33.pdf
Please help me ! Thanks

 

[Esme]

U r given some values,
Total number of Females (Fn) = 12
Total number of ppl who watch "Kids andKops" (Kn) = 16
Number of female who watch "Kids and Kops" (In) = 3
now
P(Fn or Kn or both) = 12/30 +16/30 + 3/30 (Since 3/30 signifies for the intersection of female and who watch "KIDS and KOPS"
calculate and u will get your answer.....

No i dont get the ans. 12/30+ 16/30 + 3/30 = 31/30
The ans is 5/6.

 

[Dug]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w07_qp_1.pdf Question 11 .. part 2 3 4 and 5 wid da concepts plz :/

From Part i u get f(x)=2(x-2)^2 +3

ii) Its a rule for completing square form:
f(x)=a(x-p)^2 + q
where p and q are the x and y coordinates of the vertex respectively.
Remember that when you are taking out the x-coordinate from this equation its going to be equal to p and not -p
Also, equation of line of symmetry is x=p

Lets consider f(x) = 2(x-2)^2 +3
Vertex(2,3)
The function is cup-shaped therefore f(x) >= 3

iii) Because its not a one-to-one function since the parabola has 2 values of x for 1 value of y. You can sketch a rough parabola and use the horizontal line test. If at any point, the line touches the curve at 2 points then the function does not have an inverse.

iv) Divide the curve at the line of symmetry and use horizontal line test again. You will see that the test works now therefore A=2

v) Take y = 2(x-2)^2 + 3 and make x the subject.
(y+3)/2 = (x-2)^2
x = ±√((y+3)/2) +2

Now you have to decide which sign has to stay.

This was originally posted by Esme. The 'c' here represents the vertex.
And so, we get g-1(x) = -√((x+3)/2) +2

Prayers please!!

 

[Esme]

@Dug
All Rights Reserved
lol

 

[hm12]

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w11_qp_11.pdf

please explain question number 3 part (ii) and part (iii)

 

[Dug]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_qp_11.pdf

please explain question number 3 part (ii) and part (iii)

i) I assume you had no problem with the graph. The number of intersections the curve and the line make is the required answer.
iii) Use proportionality.
In 2pi there are 4 roots
In (20pi-10pi) there are x roots.

x = 4 x 10 / 2

 

[hm12]

i) I assume you had no problem with the graph. The number of intersections the curve and the line make is the required answer.
iii) Use proportionality.
In 2pi there are 4 roots
In (20pi-10pi) there are x roots.

x = 4 x 10 / 2

oh okay thats easy thanks for your help

 

[roadtrip9o9]

thanks ... could u just tell in general or by some notes ... how do we find a range and that a value thingy ... like i mean to ask the concept behind it :/

 

[Dug]

thanks ... could u just tell in general or by some notes ... how do we find a range and that a value thingy ... like i mean to ask the concept behind it :/

a value thingy?
In a quadratic equation, you have to consider the shape of the curve and state the range accordingly.
ax^2 + bx + c =0
Find the vertex by either of the 3 methods i.e Completing square, x=-b/2a , Derivatives.
If a>0 (cup shaped), then f(x) >= y-coordinate of the vertex.
If a<0 (cap shaped), then f(x) =< y-coordinate of the vertex.

If the question asks for the range in a specific domain.
e.g Find the range of f(x)=some function for the domain a =< x =< b

Inject the limits into the function and then find the x-coordinate of the vertex.
f(a) = p
f(b) = q
Now you have to check if a vertex lies in the given domain.
Use x=-b/2a
If this value of x does not exist in the stated domain, then p and q are your limits for the range.
Suppose, p=3 and q=-2
3 >= f(x) >= -2
If this value of x does exist in the domain, then put this value into f(x).
So, f(-b/2a) = r
You got the limits. Lets suppose values for p,q and r.
Say, p=3 , q=5 and r=-2
The range will be 5>= f(x) >=-2.
See you have to consider the extreme values you get.

Whether or not you have to put an equal sign with the inequalities, depends on the domain provided. In this case because we do have the '=' signs with the domain, we put them with the range too.

That was all about quadratics.

 

[hm12]

http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w11_qp_11.pdf
http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_w11_ms_11.pdf
please explain question 9 part(ii) i don't get whats done in the marking scheme

 

[Mosamali]

hi,
how would you find the range of a function in this question
q3ii) http://www.xtremepapers.com/papers/...S Level/Mathematics (9709)/9709_s10_qp_13.pdf