Mathematics: Post your doubts here!

[masterex567]

I have one question on the marking of these papers, do they give all marks if answer is correct or the correct method should also be there?
What if the method is different from the one in marking scheme but answer is correct, is full credit awarded then?

 

[reem maqlad]

How Do I Factorize ?

 

[XtremeStudent1999]

AsSalamoAlaikum Wr Wb...

Stuck somewhere in Maths?? Post your queries here! Members around will help you InshaAllah.

NOTE: If you have any doubt in the pastpper questions, then kindly post the link to the paper!

May Allah give us all success in this world as well as the HereAfter...Aameen!!

SEQUENCES-Points to remember:
Many people find it hard, but to be honest it's just more of logic..that's all!

Sequences!

Using log for indices.

YEAH ,, Wa'alaikumusalaam... SPECIMEN PAPER 2015 LAST QUESTION...(DARN IT LOST ALL 9 MARKS )
#CONFUSING

 

[Kiara P.]

How Do I Factorize ?

You mainly just bring all multiples of the timetable that has the number you're factorizing as in when we say for example factors of 36 then it would be 1,2,3,4,6,9,12,18.. all these numbers has in their timetable a number that's gives a product of 36 as in 2 it's 2x18. I hope you get it!

 

[qurratul ain yafu]

can u show me how to solve an inequality (the hard ones) plz

 

[loaie Amgad]

guys , do we have the log function in maths 0580 extended in our syllabus????

Thanks in advance.........

 

[Mr.Physics]

guys , do we have the log function in maths 0580 extended in our syllabus????

Thanks in advance.........

You should know how to carry out log functions because there are some indices questions that are really hard !!

 

[masterex567]

I have one question on the marking of these papers, do they give all marks if answer is correct or the correct method should also be there?
What if the method is different from the one in marking scheme but answer is correct, is full credit awarded then?

can anyone help me with this?

 

[loaie Amgad]

You should know how to carry out log functions because there are some indices questions that are really hard !!

Thanks for your help
Furthermore, I need an example of how to use it
can anyone quote a question and solve it relating to log function .............
Thanks in advance (again).....

 

[reem maqlad]

You mainly just bring all multiples of the timetable that has the number you're factorizing as in when we say for example factors of 36 then it would be 1,2,3,4,6,9,12,18.. all these numbers has in their timetable a number that's gives a product of 36 as in 2 it's 2x18. I hope you get it!

Thank You IT WAS VERY HELPFUL

 

[XtremeStudent1999]

MAN ... I WISH IGCSEs NEVER EVEN EXISTED!!!! #tiredofstudying #needtogetalife #yaALLAH HELP ME!!!

 

[Kiara P.]

You welcome anytime sister

 

[lina1999]

hey
what will happen if i dont attend one exam paper for example maths paper 2 will i get a zero for it or they wont count the whole exam??

 

[Kiara P.]

hey
what will happen if i dont attend one exam paper for example maths paper 2 will i get a zero for it or they wont count the whole exam??

I think you would just like take a zero on that paper,but nope paper 4 if you did it will be counted but you would lose the A*/A range threshold and be going for a D or a C.

 

[masterex567]

How do you do number 19 in winter 2013, paper 22.
It's about vectors in a regular hexagon. please explain and help

 

[NOneed2speedd]

assalamulaikum everyone!
does anyone here know anything about may/june 2015 maths or chemistry (both extended) ? PLEASE help if you do know anything!!
i'm done with my ict practicals 2015 session if you need any help let me know
and is any one having their paper 2 before 7 may(am) and their paper 4 before 11 may(am) ???? if yes,then please tell me i'd really appreciate it!
thanks
jazakumallah khair and inshallah our exams are gonna be great!

If u get to knw anything then plz do let me knw too... i am also having my p2 and p4 on same day

 

[AnonymousX9]

Oct/Nov 2014 Paper 22, question 16 b(ii), please help, I tried a lot of times but still didn't get it.

Also, Oct/Nov 2014 Paper 42, question 10(c). Tried 10 times, still couldn't understand *sigh*.

 

[masterex567]

For

Oct/Nov 2014 Paper 22, question 16 b(ii), please help, I tried a lot of times but still didn't get it.

Also, Oct/Nov 2014 Paper 42, question 10(c). Tried 10 times, still couldn't understand *sigh*.

For question 10(c):

Alright first we gather the possibilities. So to get to the 100th place, these are the possible ways:

1. Roll a 3.
2. Roll a 2 on first throw and then a 4 on second throw.
3. Doesn't roll a 2 or 3 on first throw and then rolls a 3 on second throw.

Now we gather the probabilities for each of these cases.
To roll a 3, he can either roll a 1 and 2 on die, or a 2 and 1 on die. Which is (1/6 * 1/6) + (1/6 * 1/6).
Therefore to roll a 3, the probability is 2/36.

Next, for roll a 2 on first throw and 4 on second.
To roll a 2, he needs to roll 1 and 1 on die. Therefore it is (1/6 * 1/6). which is 1/36.
Now to roll a 4 there are numerous possibilities. He can roll a 1 and 3, or a 3 and 1, or a 2 and 2. Calculate the probabilities for this as follows:
(1/6*1/6) + (1/6*1/6) + (1/6*1/6).
Therefore probability for rolling a 4 is 3/36.

Next, we find probability for not rolling a 2 or 3. Which is the same as 1 - (probability of rolling 2 or of rolling 3).
1 - (1/36 + 2/36). This is (1 - 3/36) or 33/36. same thing. And now probabibility of rolling a 3 on second throw will be 2/36 as calculated before.


FINALLY. We calculate all these.
So probabibility of getting a 100 is:
Probability of rolling a 3, OR, not rolling 2 or 3 on first throw, AND rolling 3 on second, OR probability of rolling a 2 on first throw AND 4 on second. Remember OR is adding. AND is multiplying.
[2/36] + [1-(3/36) * 2/36] + [1/36 * 3/36]

And that gives the final answer of 47/432. If you check the calculation above is similiar to one in marking scheme!

If you need any clarification on this, let me know.
Cheers

 

[loaie Amgad]

For


For question 10(c):

Alright first we gather the possibilities. So to get to the 100th place, these are the possible ways:

1. Roll a 3.
2. Roll a 2 on first throw and then a 4 on second throw.
3. Doesn't roll a 2 or 3 on first throw and then rolls a 3 on second throw.

Now we gather the probabilities for each of these cases.
To roll a 3, he can either roll a 1 and 2 on die, or a 2 and 1 on die. Which is (1/6 * 1/6) + (1/6 * 1/6).
Therefore to roll a 3, the probability is 2/36.

Next, for roll a 2 on first throw and 4 on second.
To roll a 2, he needs to roll 1 and 1 on die. Therefore it is (1/6 * 1/6). which is 1/36.
Now to roll a 4 there are numerous possibilities. He can roll a 1 and 3, or a 3 and 1, or a 2 and 2. Calculate the probabilities for this as follows:
(1/6*1/6) + (1/6*1/6) + (1/6*1/6).
Therefore probability for rolling a 4 is 3/36.

Next, we find probability for not rolling a 2 or 3. Which is the same as 1 - (probability of rolling 2 or of rolling 3).
1 - (1/36 + 2/36). This is (1 - 3/36) or 33/36. same thing. And now probabibility of rolling a 3 on second throw will be 2/36 as calculated before.


FINALLY. We calculate all these.
So probabibility of getting a 100 is:
Probability of rolling a 3, OR, not rolling 2 or 3 on first throw, AND rolling 3 on second, OR probability of rolling a 2 on first throw AND 4 on second. Remember OR is adding. AND is multiplying.
[2/36] + [1-(3/36) * 2/36] + [1/36 * 3/36]

And that gives the final answer of 47/432. If you check the calculation above is similiar to one in marking scheme!

If you need any clarification on this, let me know.
Cheers

WoW ,,,, Brilliant explanation
thanks for it
Even though I am not the one who asked but it helps a bunch .......
Thaaaaaaaaanks ...... best clarification of probability......

 

[AnonymousX9]

Thank you so much. Your explanation was amazing!
Although I do have one doubt, what if he gets 2 in his first throw and lands on 96 and gets a 3 again? Why don't we take that into account? Or is it because of the fact that we have to consider ONLY the possibilities which will make sure that he wins in his NEXT 2 throws?

Thanks once again!