Mathematics: Post your doubts here!

[MMK95]

http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Mathematics (0580)/0580_s12_qp_41.pdf

Q 10 (b) : how can i get the upper radius ?
--------------------------------------------
In similarity , using the k , k^2 or k^3
how do i know when are the given numbers in the question are just K , k^2 or k^3 ?

use this formula for similar figures

(V1/V2) = (Side1/Side2)^3

by assuming that the volume of the removed cone is x and the answer of Q10 a is 2035.8
(2035.8/x) = (24/8)^3
(2035.8/x) = (13824/512)
x = 2035.8/27
x = 75.4
Volume of the remaining solid = 2035.8 - 75.4
= 1960.4
= 1960 ( shown)

 

[mrdarkevil19989]

I am having a doubt in question 6 june 2009 math paper 4 http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Mathematics (0580)/0580_s09_qp_4.pdf

 

[Ahmed Al Hilali]

t

use this formula for similar figures

(V1/V2) = (Side1/Side2)^3

by assuming that the volume of the removed cone is x and the answer of Q10 a is 2035.8
(2035.8/x) = (24/8)^3
(2035.8/x) = (13824/512)
x = 2035.8/27
x = 75.4
Volume of the remaining solid = 2035.8 - 75.4
= 1960.4
= 1960 ( shown)

Thanks A Lot

 

[mrdarkevil19989]

use this formula for similar figures

(V1/V2) = (Side1/Side2)^3

by assuming that the volume of the removed cone is x and the answer of Q10 a is 2035.8
(2035.8/x) = (24/8)^3
(2035.8/x) = (13824/512)
x = 2035.8/27
x = 75.4
Volume of the remaining solid = 2035.8 - 75.4
= 1960.4
= 1960 ( shown)[/q

use this formula for similar figures

(V1/V2) = (Side1/Side2)^3

by assuming that the volume of the removed cone is x and the answer of Q10 a is 2035.8
(2035.8/x) = (24/8)^3
(2035.8/x) = (13824/512)
x = 2035.8/27
x = 75.4
Volume of the remaining solid = 2035.8 - 75.4
= 1960.4
= 1960 ( shown)

plzzzzzzzzzz would solve question 6 june 2009 paper 4 http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Mathematics (0580)/0580_s09_qp_4.pdf

 

[mrdarkevil19989]

plzzzzzzzzzzzzzz someone help me in question june 2009 paper 4 http://papers.xtremepapers.com/CIE/Cambridge%20IGCSE/Mathematics%20(0580)/0580_s09_qp_4.pdf ​

 

[MMK95]

plzzzzzzzzzzzzzz someone help me in question june 2009 paper 4 http://papers.xtremepapers.com/CIE/Cambridge%20IGCSE/Mathematics%20(0580)/0580_s09_qp_4.pdf ​

Which part??????????

 

[mrdarkevil19989]

Which part??????????

part a

 

[MMK95]

part a

Area of ABC = Area of ABD + Area of DBC

40 = [1/2 (x+6)(x+1)] + [1/2 (x+2)(x+1)]
40 = (x^2 +7x + 6)/2 + (x^2 +3x + 2)/2
40 = (2x^2 + 10x + 8)/2
40 = x^2 +5x + 4
x^2 +5x +4 - 40 = 0
x^2 + 5x - 36 = 0 (shown)

 

[mrdarkevil19989]

thank u
and plz would u do question 2 d

 

[MMK95]

thank u
and plz would u do question 2 d

mean = (sum of fx)/(sum of f)
2.95 = sum of fx/60
sum of fx = 60 * 2.95
= 177
to get the fx of first 50 rolls multiply you answer of c with 50
2.96 * 50 = 148

fx for the 10 rolls = 177 - 148
= 29

mean = sum of fx/sum of f
= 29/10
= 2.9

 

[mrdarkevil19989]

plz would u explain the bearing question for me

 

[ZaqZainab]

A quadratic sequence is a sequence where the 'second difference' is constant.

E.g. 3, 5, 8, 12, 17, ...

The 'first differences' are 2, 3, 4, 5, ... and the second difference is 1 (constant) so this is a quadratic sequence.

The nth term of a quadratic sequence is always in the form an^2 + bn + c.

a is the second difference divided by 2. You can find b and c by substituting values and solving simultaneous equations (you're not expected to this method for IGCSE but they may guide you through it).

So it is not completely necessary to know the method for finding the nth terms of quadratic sequences but it is useful to know. They might ask you simple ones like 1, 4, 9, 16, ... or 2, 6, 12, 20, ...

My teacher never taught me this :'( Thank you

 

[Tobi Balogun]

0580/_w10_qp_42
question 10 cii.
Please help . completely lost

 

[notnek01]

plz would u explain the bearing question for me

From which paper?

 

[notnek01]

0580/_w10_qp_42
question 10 cii.
Please help . completely lost

Using the information given in the question we have

(1) -33+x=y
(2) x+y=z --> y=z-x
(3) y+z=18 --> z=18-y

Can you see where I got these equations from? Next, substitute z from equation (3) into equation (2) then substitute y from equation (2) into equation (1).

 

[AlphaWolf]

Hello, I need help in two problems:

i) How do you perform a stretch and a shear. How to find their invarient line and shear/stretch factor?

ii) how to find the matrice which represents a transformation.

Please help as i have my paper 4 in 2 days.

 

[notnek01]

Hello, I need help in two problems:

i) How do you perform a stretch and a shear. How to find their invarient line and shear/stretch factor?

ii) how to find the matrice which represents a transformation.

Please help as i have my paper 4 in 2 days.

That's too much to explain in a forum. I've uploaded my revision notes on transformations, let me know if you have any questions.

 

[~P!@$m0~]

so is a there any such thing as negative integers..? like.. ( -1, -2, -3 ...) ??

 

[notnek01]

so is a there any such thing as negative integers..? like.. ( -1, -2, -3 ...) ??

Integers are whole numbers that could be positive, negative or zero.

 

[~P!@$m0~]

"find a formula for the sequence 5, 14, 29, 50, 77, ... Since you know that the sequence is quadratic, you are looking for an expression an^2 + bn + c for the n-th term. With n = 1 we have a + b + c = 5, with n = 2 we have 4a + 2b + c = 14, and with n = 3 we have 9a + 3b + c = 29."

How do u find the formula.. i mean what are the steps u do to find it..can u show how..cuz m not getting it.. :/