Mathematics: Post your doubts here!

[syed1995]

ok look here:
P(A) = 1/3
P(B) = 5/9

are these events mutually exclusive??
plz give an explnation too like working and all cz i'm not sure if i'm doing it ryt...

also explain if they are independant events...
and are they exhaustive events...
again with the working and stuff. thanks a lot

LOL.. one can't solve it without the data... It can be both... link the question.

 

[Anika Raisa]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s12_qp_32.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s12_ms_32.pdf

Q7 iii) why is arg(1+2i) - arg(1-3i) = arg(u) ??

Anika Raisa ?

See
lets take x=1+2i n y=1-3i now there is a general rule saying: arg(x/y)=arg x - arg y

https://www.xtremepapers.com/community/attachments/cnf1-jpg.25812/

So in here u=x/y so arg u= arg x-arg y !

Hope i cud help u .... Esme.

 

[Anika Raisa]

ok look here:
P(A) = 1/3
P(B) = 5/9

are these events mutually exclusive??
plz give an explnation too like working and all cz i'm not sure if i'm doing it ryt...

also explain if they are independant events...
and are they exhaustive events...
again with the working and stuff. thanks a lot

C,
for 2 events A n B...
if P(A intersection B)= P(A)*P(B)
then A n B are independent!
If P(A intersection B )=0
then A n B are mutually exclusive!

this is the general explanation!! But like syed1995 i wud say u nid to link d question --- here u hv nt given enough data to graw conclusion u c!

 

[daredevil]

LOL.. one can't solve it without the data... It can be both... link the question.

i dnt have the link .. its in my past paper topical and the address of the papr is not given. but i'll try to send a picture of it. wait

 

[daredevil]

This is the question syed1995 Anika Raisa

 

[Anika Raisa]

oh w8! i have it done i m writinng in a min!ok!

This is the question syed1995 Anika Raisa

 

[Anika Raisa]

This is the question syed1995 Anika Raisa

C over here u got p(A)=1/3 in i
n P(B)=5/9 in ii

now A intersection B means that the score differ by 3 or more and also there product is greter than 8

so P(A intersection B)=6/36

not 0 so A n B are not mutually exclusive!!
Btwn dis is frm on06 or mj06...

Btwn post ur S1 doubts here: https://www.xtremepapers.com/commun...oubt-post-your-doubts-here.25911/#post-537193

Hope i cud be helpful!!!

 

[Anika Raisa]

STATISTICS PPL!!! POST UR DOUBTS HERE!!!!
https://www.xtremepapers.com/commun...oubt-post-your-doubts-here.25911/#post-537193

For stat ppl!!BOTH S1 n S2!!

sma786
daredevil

I see a lot of stats related posts here, anyone up for answering P3 doubts ?

 

[Esme]

See
lets take x=1+2i n y=1-3i now there is a general rule saying: arg(x/y)=arg x - arg y

https://www.xtremepapers.com/community/attachments/cnf1-jpg.25812/

So in here u=x/y so arg u= arg x-arg y !

Hope i cud help u .... Esme.

Omg yes ! Thank you... I forgot that rule !!

 

[syed1995]

This is the question syed1995 Anika Raisa

I will take a look tomorrow.. currently preparing for the computer paper tomorrow

 

[daredevil]

I will take a look tomorrow.. currently preparing for the computer paper tomorrow

np man... anika already helped out. thanks anyways and Good Luck for tommorow

 

[Anika Raisa]

no problem it happens!!!

Between Esme cud u also help me wid question no. 10 of on11 variant 33!
HERE is the link:
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_qp_33.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_ms_33.pdf

Omg yes ! Thank you... I forgot that rule !!

 

[Esme]

no problem it happens!!!

Between Esme cud u also help me wid question no. 10 of on11 variant 33!
HERE is the link:
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_qp_33.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_ms_33.pdf

Okay I'll give it a try, if I'm able to do it ..will definitely let you know

 

[Esme]

ln(x²) is not the same as [ln(x)]². Try again using the latter!

You're right .. thanks Dug! That's the mistake I was making !

 

[applepie1996]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s12_qp_32.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s12_ms_32.pdf

Q9 ii) I can't seem to get the answer, even though I think I'm integrating it right.
We have to integrate x lnx^2
I'm doing it by integration by parts but I don't get the answer as in the marking scheme..
Anyone? Please show me the workings

applepie1996

sorry i couldn't so your question
i got a little busy
but if you still don't get it
i can explain it to you

 

[Esme]

http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_w12_qp_32.pdf
http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_w12_ms_32.pdf

Q8 ii) I usually don't have problems with iteration but I don't understand what the question is asking and the marking scheme isn't very clear..
Anyone ? What do we have to do ?

 

[Esme]

sorry i couldn't so your question
i got a little busy
but if you still don't get it
i can explain it to you

It's okay
Thanks but I got my mistake

Could you help with this though ?:

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w12_qp_32.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w12_ms_32.pdf

Q8 ii) I usually don't have problems with iteration but I don't understand what the question is asking and the marking scheme isn't very clear..
Anyone ? What do we have to do ?

 

[applepie1996]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w12_qp_32.pdf
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w12_ms_32.pdf

Q8 ii) I usually don't have problems with iteration but I don't understand what the question is asking and the marking scheme isn't very clear..
Anyone ? What do we have to do ?

you put x=2 in the iterative formula that is given and see what value it converges to
so what i got is 1.86
put 1.86 in the y equation of the graph and you get y as 0.5

 

[Esme]

you put x=2 in the iterative formula that is given and see what value it converges to
so what i got is 1.86
put 1.86 in the y equation of the graph and you get y as 0.5

Yeah I did this too... but I got 1.89 and when i put it in the y equation I get 0.476.. Is it okay if I round it off to 0.5 then ??

 

[applepie1996]

Yeah I did this too... but I got 1.89 and when i put it in the y equation I get 0.476.. Is it okay if I round it off to 0.5 then ??

ummmm yeah you put in x as 2 and you get 1.893018......
now you put this value in your equation again and you get 1.867190575
keeping putting the values you get back into the equation till you get a constant answer continuously in this we keep getting 1.85855 which rounds up to 1.86