Mathematics: Post your doubts here!

[Esme]

Esme
There you go, littlecloud11 have answered this before.

Thank you so much.. finally I know now.

littlecloud11 Masha'Allah genius.. I would have never thought of working it out like that, and even my teacher couldn't explain these questions

 

[leosco1995]

Please help with this.

 

[Alice123]

Please help with this.

please excuse my handwriting

 

[leosco1995]

please excuse my handwriting

Great! Thanks for the fast reply.

 

[Esme]

please excuse my handwriting

Anika Raisa You also asked this question... there you go. Alice123 has solved it

 

[19islandprincess96]

Please help! This paper http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s07_qp_3.pdf
Question 5 part 2!
And question 8?
How do we do them?

 

[HubbaBubba]

Statistics Paper 6 Question

1. The volume of milk in millilitres in cartons is normally distributed with mean (u) and standard deviation 8. Measurements were taken of the volume in 900 of these cartons and it was found that 225 of them contained more than 1002 millilitres.
(i) Calculate the value of (u)

Can anybody tell me how they found the value of z ?

 

[iKhaled]

how can i solve question 10 omggg! someone pls help

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_s12_qp_33.pdf

 

[Silent Hunter]

http://papers.xtremepapers.com/CIE/...AS Level/Mathematics (9709)/9709_s08_qp_3.pdf

Q8 (i) ?

applepie1996
Rutzaba

or anyone?

Thanks

 

[Esme]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s08_qp_3.pdf

Q8 (i) ?

applepie1996
Rutzaba

or anyone?

Thanks

Area of triangle PTN = tanx
1/2 x TN x PN = tanx
1/2 x TN x y = tanx

dy/dx = PN/TN
TN = PN x dx/dy
TN = y x dx/dy

Now substitute TN in area of triangle
1/2 ( y x dx/dy) y = tanx
1/2 y^2 (dx/dy) =tanx
dy/dx = (1/2 y^2)/tanx
dy/dx = 1/2 y^2 cotx

Hope you got it

 

[Rutzaba]

Statistics Paper 6 Question

1. The volume of milk in millilitres in cartons is normally distributed with mean (u) and standard deviation 8. Measurements were taken of the volume in 900 of these cartons and it was found that 225 of them contained more than 1002 millilitres.
(i) Calculate the value of (u)

Can anybody tell me how they found the value of z ?

link

 

[Rutzaba]

Please help! This paper http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s07_qp_3.pdf
Question 5 part 2!
And question 8?
How do we do them?

gimme 5 mins

 

[HubbaBubba]

link

Question 1
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s09_qp_6.pdf

 

[syed1995]

HubbaBubba
1. The volume of milk in millilitres in cartons is normally distributed with mean (u) and standard deviation 8. Measurements were taken of the volume in 900 of these cartons and it was found that 225 of them contained more than 1002 millilitres.
(i) Calculate the value of (u)

Can anybody tell me how they found the value of z ?

P(x>1002)=225/900
P(x>1002)=0.25
P(z>1002-u/8)=inversePhi(0.25)
P(z>1002-u/8)=-inversePhi(0.75)
P(z<-(1002-u/8))=-inversePhi(0.75)
-(1002-u)/8=-0.674
1002-u/8=0.674
1002-u=5.392
u=996.6 Answer

 

[syed1995]

Question 1
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s09_qp_6.pdf

Done above ^^

 

[Fatima18]

http://papers.xtremepapers.com/CIE/...AS Level/Mathematics (9709)/9709_s03_qp_6.pdf
Hey guys...Can anyone explain well number 5ii and 5 iii?????Thanx!

 

[Rutzaba]

Please help! This paper http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s07_qp_3.pdf
Question 5 part 2!
And question 8?
How do we do them?

∫ 2/ u(4-u)
by partial fractions
A/ u + B/ 4-u
((((A(4-u) +B(u)))) / u(4-u)
4A -Au +Bu
compare with 2/ u(4-u)
the denominator eliminates... and we have two equations
a-b=0 since there is no term in u---i
4A =2 the term without variable
A= 1/2
b=1/2
then ∫ 1/2(u) + 1/2(4-u) for the limits 2 and 1
1/2 ln u + 1/2 ln (4-u)
1/2 ln ( u +(4-u)(-1)) note that the -1 is the differential of 4-u
minus means to divide in log
so 1/2 ln ( u/ (4-u))
out limits 2 and 1
1/2 ln (2/4-2) -1/2 ln (1/4-1)
1/2ln 1 - 1/2 ln 1/3 note that ln 1=0
0 -1/2 ln 1/3
-1/2 ln (3^-1) by log propery the power would come down
-(-1/2 ) ln 3
1/2 ln 3
sorry abt the complex numbers ive completely forgotten em ... dun frgt to pray fr me

 

[syed1995]

Rutzaba

You're awesome .. P3 looks quite hard :\

 

[Rutzaba]

Rutzaba

You're awesome .. P3 looks quite hard :\

its not hard on paper... computer freaks everyone out

 

[Rutzaba]

like i dint do 75 percent of the explaining i did here... i mean no alphabets except for variables... plus here two t0pics are involved one is integration and other is partial fractions