Mathematics: Post your doubts here!

[Thought blocker]

Can some one explain Oct'11 paper 11 functions question which asks for range. I can get 2 but mark scheme also has 10

Domain of f = 0 <= x <= 2
So for range of f put 0 instead of x and then 2 instead of x
so range will be 2<= f <= 10

 

[Glory Hunter]

That site is much of a HELP! I learn new ways outta PRACTICE!
You will come across one question of St. line, which is twisted, I know you will ask that as well, coz its all Ulta pulta method.

thanx for trhe help and yes u are right tht site iz epic

 

[Haya Ahmed]

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_w11_qp_22.pdf

Q8 (iii)

Thought blocker
ZaqZainab

 

[RoOkaYya G]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_qp_22.pdf

Q8 (iii)

Thought blocker
ZaqZainab

do it by graphical (range) method :
-1<=cosx<=1
3* the Rcos formula u got
-1*3root34<=3root34(cos theta+30.9)<=1*3root34
so least value is -1*3root34
which = -3root34 (theres a minus sign!) ^_^

 

[asadalam]

Q.Find the equation of the normal to the curve y=2x^2 + 3x +4 which is perpendicular to the line y=7x-5

Any help?

 

[RoOkaYya G]

Q.Find the equation of the normal to the curve y=2x^2 + 3x +4 which is perpendicular to the line y=7x-5

Any help?

is the answer 7y+x=64?

 

[Faaiz Haque]

device the formula n make h subject of formula
using the formula for volume of the shape (cross sectional area * height)
replace h in volume
solve

QU 5 use similarity property find the measurements

Thanks very much. I did the question 9, i'd appreciate it if you solved the second one, I can't seem to arrive at the correct answer.

Q5)http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w05_qp_1.pd

 

[RoOkaYya G]

Thanks very much. I did the question 9, i'd appreciate it if you solved the second one, I can't seem to arrive at the correct answer.

Q5)http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w05_qp_1.pd

12/6= (12-h)/r ----> (using similarity.big triangle n small triangle on top of the cylinder)
make h subject of formula n ull get ---> h=12-2r

volume of cylinder =pi*r^2*h
replace h=12-2r in the formula for volume of cylinder ull get ----> 12*pi*r^12 - 2*pi*r^3

 

[3rbabi__]

someone helps me out plz , with
mechanics , 0ct/nov 2012 , 41 , last question
http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_w12_qp_41.pdf

 

[Biocalife]

Assalamoualaikum,

Im having problem with June 2014 Paper 3 Number 8.. Could someone explain thanks.

 

[RoOkaYya G]

someone helps me out plz , with
mechanics , 0ct/nov 2012 , 41 , last question
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w12_qp_41.pdf

(i)
using power=force*velocity (p=fv)
v=12
p=17280
so f=17280/12 =1440

using newtons laws of motion
f=ma
(f-resistance)=ma
(1440-960)=1200*a
a=0.4

(ii)
since speed is constant, acc. =0

using newtons laws of motion
f=ma
(p/v)-resistance=ma
[(p/v)-960]=1200*0
(17280/v)=960
v=18 (HENCE SHOWN) ^_^

 

[asadalam]

is the answer 7y+x=64?

Yup

 

[RoOkaYya G]

Assalamoualaikum,

Im having problem with June 2014 Paper 3 Number 8.. Could someone explain thanks.

gimme the link plz

 

[RoOkaYya G]

Yup

yayy!! ^_^ i blacked out for an instant
ive got maths p1 on 8th oct
ty!

 

[asadalam]

yayy!! ^_^ i blacked out for an instant
ive got maths p1 on 8th oct
ty!

Good luck for your paper.Could you please explain to the method with which you solved this?If you could post a screenshot of your working on a page it would be better ^^

 

[RoOkaYya G]

Good luck for your paper.Could you please explain to the method with which you solved this?If you could post a screenshot of your working on a page it would be better ^^

Well i understood the quest in 2 different ways so i worked it out n i got 2 answers
i thought this one is better coz it was more "normal"
uhm should i write it here or shld i make i explain it live to u on twinddla whiteboard?

 

[asadalam]

Well i understood the quest in 2 different ways so i worked it out n i got 2 answers
i thought this one is better coz it was more "normal"
uhm should i write it here or shld i make i explain it live to u on twinddla whiteboard?

The latter please.It gets too confusing to work out equations here,especially due the powers and such

 

[Biocalife]

Right here Thanks

 

[RoOkaYya G]

The latter please.It gets too confusing to work out equations here,especially due the powers and such

open this link
http://www.twiddla.com/1787175

 

[RoOkaYya G]

Right here Thanks

-___________- theres a lot to write

*sigh*
(i)
use product rule n differenciate y=xcos0.5x
dy/dx=(cos*0.5x)-(0.5*x*sin0.5x)
d2y/dx2= -0.5*sin0.5x - [ dy/dx of the part 0.5*x*sin0.5x using product rule again)

d2y/dx2 = (-0.5sin*0.5x) - (0.5sin*0.5x) - (0.25xcos0.5x)
= -sin0.5x - 0.25 xcos0.5x


replace the d2y/dx2 in the equation given...it will be = 0

(ii)
integrate the f(x) using integration by parts (LATE)
use limits on x axis which r x=0 and x=pi
replace n solve