Author Topic: CIE AS LEVEL Math..  (Read 1566 times)

Offline Stay10

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CIE AS LEVEL Math..
« on: May 09, 2010, 08:41:52 am »
hey every1..needed sum help in math..is there any notes or reference materials tht could help me understand the range and domain of a function (basic overview)..gone through lotz of past papers nd found those question question tricky..so if any1 could explain me or any reference would be really appreciated...need it as soon as possible..nt much time left..Thanks  :)

Offline Meticulous

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Re: CIE AS LEVEL Math..
« Reply #1 on: May 09, 2010, 08:45:20 am »
Post your questions. I will be happy to help.

Try www.astarmathsandphysics.com

Offline Stay10

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Re: CIE AS LEVEL Math..
« Reply #2 on: May 09, 2010, 08:51:36 am »
..Thanks 4 the site..ll go through it..but i mean like i dont know wht it means..both range nd domain..there is a question in paper 12 of oct/nov 2009..no. 4..would really appreciate the explanation..

Offline Stay10

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Re: CIE AS LEVEL Math..
« Reply #3 on: May 09, 2010, 06:33:54 pm »
came across another question from the paper oct/nov 2008, question 7 (i) & (ii)..w8in 4 the reply..

Freaked12

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Re: CIE AS LEVEL Math..
« Reply #4 on: May 10, 2010, 01:29:49 am »
came across another question from the paper oct/nov 2008, question 7 (i) & (ii)..w8in 4 the reply..

Show that A =
(? + 4)x2 ? 160x + 1600
divided by pie

So the perimeter according to the question is 80 of both the shapes so as a result
x + x + x + x + 2(pie) r
4x+ 2 (pie)r=80
2(2x+ (pie)r)=80
2x + (pie) r= 40
We make r the subject
r= 40/(pie) - (2/(pie))x

we now substitute the r value into the equation (the area of both sides)
A= x square plus (pie) r square
x square + (pie)(40/(pie) - (2/(pie))x)square
x square + pie(1600/pie^2 - 16.21x + 4/pie^2 x^2)
which if you calculate
(1600- 16.21x pie^2 + 4 x^2 + pie x^2)/pie
((4+ pie)x^2 +1600 - 160x)/ pie

2) it depends on whether u have taken r or x the subject
in this case r
so we differentiate
(2((pie) +4) x -160)/pie=0<br />pie * 0=0 so 2x(pie +4)-160=0<br />2x(pie +4)=160<br />x(pie +4)=80<br />x=80 divided by pie plus 4<br />x=11.2
« Last Edit: May 10, 2010, 01:41:26 am by Freaked12 »

Offline Stay10

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Re: CIE AS LEVEL Math..
« Reply #5 on: May 10, 2010, 04:50:41 am »
Thanks.. :)

Offline Stay10

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Re: CIE AS LEVEL Math..
« Reply #6 on: May 10, 2010, 04:52:57 am »
came across another question from the same paper..question 9..dont get the markin scheme..ll be w8in..

Offline immortal

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Re: CIE AS LEVEL Math..
« Reply #7 on: May 10, 2010, 08:07:17 am »
9>Area of region
    Area of square-area under graph
     (2*1)-(Integration of (3x+1)1/2 by 0,1)
     2-[2/9*(3X+1)3/2],0,1
     =4/9
ii> Volume of region
     volume of cylinder-volume under graph
     Pi*2*2-Pi integration of [(3x+1)1/2]2 to 0,1
     4Pi-Pi[1/6*(3x+1)2] to 0,1
     4Pi-Pi[8/3-1/6]
     4Pi-2.5Pi   
     1.5Pi

iii> Differentiate da eqn & substitute point of x to find da gradient
     for x=1  m=3/4                                        for x=0   m=3/2
tanQ=3/4                                              tanQ=3/2
Q=36.87                                                           56.31
Thare4 Acute angel =56.31-36.87
                           =19.4
[tanQ because gradient is also =y/x]
                         
Life is short...so live it to da fullest :)

Offline Stay10

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Re: CIE AS LEVEL Math..
« Reply #8 on: May 10, 2010, 09:14:48 am »
Thank You ! :)
« Last Edit: May 10, 2010, 09:36:24 am by Ari Ben Canaan »

Offline Meticulous

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Re: CIE AS LEVEL Math..
« Reply #9 on: May 10, 2010, 09:30:04 am »
That's considered as SPAM I guess. Posting with smileys only. Check with a moderator/ an administrator.

Offline Stay10

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Re: CIE AS LEVEL Math..
« Reply #10 on: May 10, 2010, 04:29:38 pm »
is tht so!!..well srry than..never thought this waz the case..