IGCSE MATHS Doubts

[thenewkid™]

as they both are similar triangles, their respective sides are in proportion

y/y+2 = (2y-1)/(y+1)

simplify this equation to get

y^2 - 4y - 2 = 0

ooooooooooooo now i see. Thanks

[djwaqar*]

Question2.C may/june 2006 paper4
How to solve this question
i have been tryiing to solve it from the past 20 mints

[ksitna]

i dont get how they did this

Factorise completely m^4n ? 16n^5.

help plz!

[Ghost Of Highbury]

help plz!

plz check the question before u post it...wat does the "?" mean...

[NidZ- Hero]

Question2.C may/june 2006 paper4
How to solve this question
i have been tryiing to solve it from the past 20 mints

hey same doubt here de last part is cofusin can any1 help wid this
thanku

[saleemsamer]

can some1 plz explain jun 2007 p4 q 2f and 4 c-e 

[mdwael]

They may sound a stupid question but to me its not. Its this question in summer 2000 paper 4 page 7 c(i) part it says "explain why the point (60,280) is on the curve?" this is the first time I face this kind of question, I was hoping someone could explain it to me
By the way the MS says its "end of interval is 60, 20+40+200"

Please answer my question, before I start headbutting the walls

[thenewkid™]

Question2.C may/june 2006 paper4
How to solve this question
i have been tryiing to solve it from the past 20 mints

for part c multiply the area of the cross-section by 40
as for the surface area calculate the area of each of its faces and add them together

[Vin]

um.. i still dont get it... can u elaborate a bit more. By the way the ans in the ms is 2 days 13 hours

sorry im on a real hurry doin french maths together !! im sorry if u see again the working is right .. so wat didnt u understand ??

When the pool is emptied, the water flows through a cylindrical pipe of radius 12.5 cm.
so the volume of pool is emptied i.e

volume of pool = 1512 m3 * 100 *100 *100
=1512000000 cm3

The water flows along this pipe at a rate of 14 centimetres per second.

so the area of pipe is pi * 12.5² =490.874 cm2
flows at 14cm/s   so volume per second  = 490.874 cm2 * 14cm/s  
=   6870 cm3

Calculate the time taken to empty the pool.
Give your answer in days and hours, correct to the nearest hour.

volume emptying
---------------            
rate of vol emptying

=1512000000 cm3
-----------------
    6870 cm3/sec

=ans / 60(min) * 60(hrs) *24

=2.5473 days
=2 days 13 hrs

[Ghost Of Highbury]

hey same doubt here de last part is cofusin can any1 help wid this
thanku

look at diagram 2

the shape ABO has an area of = 90/360 * 144pi = 113

area of the horizontal rectangle = (12+10=22) * (18-12=6) = 132

area of the BOCG = 12*10 = 120

total = 365

365*40 = 14600cm^3

[ksitna]

plz check the question before u post it...wat does the "?" mean...

oh sorry
its minus

[Vin]

tht gives the area of "rectangle" BCAE ( u visualise it by 'removing' tht part from the fig. )   

[saleemsamer]

can some1 plz explain jun 2007 p4 q 2f and 4 c-e

plz help

[Ghost Of Highbury]

@saleesameer - hold on..answering urs now..

[saleemsamer]

@saleesameer - hold on..answering urs now..

Thank You its just tht im abit stressed