Author Topic: IGCSE MATHS Doubts  (Read 129840 times)

Offline Saladin

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Re: IGCSE MATHS Doubts
« Reply #855 on: May 18, 2010, 10:46:35 am »
yes, provided u have do the other paper well..

Which question are you up to?

Offline Ghost Of Highbury

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Re: IGCSE MATHS Doubts
« Reply #856 on: May 18, 2010, 11:06:06 am »
I have so many questions to ask all of you..
and all of them comes from Nov 07/paper 4
http://www.freeexampapers.us/IGCSE/Maths/CIE/2007%20Nov/0580_w07_qp_4.pdf
here are the question :

Q2 (a)(vi)
Q3 (b) (c) (f)
Q4 (b) (c)
Q5 (b) (c)(v)
Q6 (b)(ii)(iii)
Q7 (d)(ii) (e)
Q8 (b)(c)(d)(e)
Q9 (b)(v)(vi)  (d)

Please answer it ASAP!
Tomorrow is the exam!!



@Engraved/Dude - Start solving these...ill join u soon, solving the previous ones posted by "big mac"
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Offline LM

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Re: IGCSE MATHS Doubts
« Reply #857 on: May 18, 2010, 11:09:35 am »
@Engraved/Dude - Start solving these...ill join u soon, solving the previous ones posted by "big mac"
I did do the whole paper...
those are the only questions left...
you see I need all the help....
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Offline Vin

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Re: IGCSE MATHS Doubts
« Reply #858 on: May 18, 2010, 11:17:41 am »
I did do the whole paper...
those are the only questions left...
you see I need all the help....

i'd typed out till ques 6 !!.. im using my laptop n it shut down unexpectedly !!! =@ aargh !! all waste im sorry i might not be able to help  i need to study =\

Offline Ghost Of Highbury

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Re: IGCSE MATHS Doubts
« Reply #859 on: May 18, 2010, 11:23:12 am »
I did do the whole paper...
those are the only questions left...
you see I need all the help....

2avi) this means that the order shud be like this : Not from 5th grade, not from 5th grade, from 5th grade

         Students not from 5th grade = 24. Total = 28

        first student not from 5th grade = 24/28

        second student not from 5th grade = 23/27 (23 because 1 student has already been picked, 28-1 = 27)

        third student is a fifth grader = 4/26 (26 because 2 students hav already been picked)

       (24/28)^2 * 4/26 = 92/819

3b) arrange it in the form of y = mx + x where 'm' is the gradient and 'c' is the y-intercept.

      y = 4-x ----> y = -x + 4 ---> y = -1(x) + 4

    thus m = -1.

3c) this means find the x-values for which the point on the curve has a negative gradient. in this, a parabola, all points in the part of the curve in the second quadrant has a negative gradient. Thus, when x<0, gradient = negative.

3f)  apply x = +/- sqrt(b^2 - 4ac)/2a

u shud get 1.3 and -2.3

 The answers i.e 1.3 and -2.3 are the x-cordinates of the point B and A respectively.

y = 4-x

y = 4-1.3 = 2.7

y = 4-x

y = 4+2.3 = 6.3

A - (-2.3, 6.3)         B - (1.3, 2.7)

(x1+x2)/2 = (-2.3+1.3)/2 = -0.5

(y1+y2)/2 = (6.3+2.7)/2 = 4.5

midpoint = (-0.5,4.5)


4b) Volume of water in the first diagram = pi*8^2*8 = 1608.5
      
   Total volume of the two spheres = 180*2 = 360cm^3

Total volume of spheres and water = 1968.5

pi*8^2*h = 1968.5

h = 1968.5/64pi = 9.79

4c) 4.8g = 1cm^3

     1000g = 1000/4.8 = 208.33cm^3

     4/3pi*r^3 = 208.33

    r = cube root of 49.73 = 3.67

5b) 2*0.5*8×’5.74’+2*0.5*6×’6.32’ +8×6 = 131.84

5c) the triangle PHN divides the pyramid into 2. thus, ans = PHN

6bii) Angle BDC = 100-58.6 = 41.4

     (BC)^2 = 182 + 302 - 2*18*30*cos 41.4 = 1224 - 810.11 = 414

     BC = sqrt(414) = 20.3m

biii) area of triangle ADB + BDC = 0.5 * 26 *30sin'41.4' + 0.5 *18* 30sin'41.4' = 436

7dii) so the new co-ordinates are
(8,6) --> (4,3)
(10,12)--> (5,6)
(6,10) --> (3,5)

plot them.

if u observe carefully, ull see dii) it is an enlargement of factor 0.5 and the center (0,0)

e) check the diagram

8b) 3/(2x-1) + 1
 
     (2+2x)(2x-1)

c) y = 3/x +1
    x=3/y + 1

    x-1 = 3/y
    xy -y = 3

    y(x-1) = 3

    y = 3/(x-1)

   g-1(x) = 3/(x-1)

d) h(3) = 8
    h(8) = 2^8 = 256

e) g(-24/7) = 0.125

    h(x) = 0.125

    2^x = 0.125

    2^x = 2^(-3)

    x = -3

9bv) 3^(n-1)

  bvi) Sequence S - Sequence T = (n+1)^2 - 3^(n-1)

d) 3^(n-1) = 177147= 3^11

   n-1 = 11

    n= 12

------------------------------------------------------------
« Last Edit: May 18, 2010, 12:17:08 pm by A@di »
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Offline pap19

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Re: IGCSE MATHS Doubts
« Reply #860 on: May 18, 2010, 11:32:55 am »
pls tell me how to do oct/nov paper 4 maths 2000 question #2 c part......

Offline Ghost Of Highbury

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Re: IGCSE MATHS Doubts
« Reply #861 on: May 18, 2010, 11:37:29 am »
pls tell me how to do oct/nov paper 4 maths 2000 question #2 c part......

gotta wait dear..hav to complete 15 more questions in toto..
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Offline pap19

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Re: IGCSE MATHS Doubts
« Reply #862 on: May 18, 2010, 11:46:50 am »
pls answer my question fast...

Offline Malak

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Re: IGCSE MATHS Doubts
« Reply #863 on: May 18, 2010, 12:03:32 pm »
How do u find Meadian? From the table??
thx
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Offline Vin

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Re: IGCSE MATHS Doubts
« Reply #864 on: May 18, 2010, 12:17:13 pm »
How do u find Meadian? From the table??
thx

which one r u talkin abt ??

Offline Ghost Of Highbury

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Re: IGCSE MATHS Doubts
« Reply #865 on: May 18, 2010, 12:18:19 pm »
pls tell me how to do oct/nov paper 4 maths 2000 question #2 c part......

upload the pic/paper..
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Offline Vin

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Re: IGCSE MATHS Doubts
« Reply #866 on: May 18, 2010, 12:24:23 pm »

here Aadi i know how to find the answer but i cant find the equation for it .. i 'll try once again ..

Offline Malak

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Re: IGCSE MATHS Doubts
« Reply #867 on: May 18, 2010, 12:35:04 pm »
which one r u talkin abt ??

In General...I jst wanna knw the basic method for finding it.. :)

And also...How do u find the invariant line for shear and strech..is it always x or y axis?  ???
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Offline Ghost Of Highbury

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Re: IGCSE MATHS Doubts
« Reply #868 on: May 18, 2010, 12:37:01 pm »
pls tell me how o do question 2 part b n c and full question 3 of maths paper 4 oct/nov 2000

gotta find the determinant first = 5t^2 -6t

thus the inverse...

(5t/5t^2-6t    -6/5t^2-6t)   = (-5t 6)
(-t/5t^2-6t      t/5t^2-6t)      (t  -t)

that means 5t/5t^2-6t = -5t

therefore, 5t^2-6t = -1

-5t^2 + 6t = 1

-5t^2 + 6t -1 = 0

t = 1/5,1



« Last Edit: May 18, 2010, 12:40:41 pm by A@di »
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Offline mdwael

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Re: IGCSE MATHS Doubts
« Reply #869 on: May 18, 2010, 12:41:34 pm »
Anybody knows where to find the markscheme for paper 4 maths summer year 2000?
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