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I'm an IGCSE Maths Teacher - Post your questions here.

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should sequences always be in this bracket form or can they be expanded cause in this answer it says n(n +1) π oe final answer
SC1 for a quadratic expression
e.g.n2 + n π
SC1,meaning they would give us only one mark
I know how to find the sequence i just want to know the format it should be written in like in bracket or expanded
im talking about this Q if you need this infomation,http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Mathematics (0580)/0580_s12_ms_43.pdf q.11 d
oe means 'or equivalent' so anything equal to n(n +1) π would get the marks.
 
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sir im confused with translation
how to translate the object by a given vector
the ans is always something different :mad:
any easy way?
 
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Hello,

It's getting close to exam time and I'm sure there are many past paper questions that students are having difficulty with. I noticed that most questions in other threads go unanswered so I thought I'd make this thread that only contains past paper questions.

So if you have an IGCSE Maths past paper question please give the i) year ii) paper number and iii) question number. Also, you must post all your working/ideas. If you don't tell me where you're up to, I can't (and won't) help you.
 
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This has been asked a few times so I'll write a full answer:

For quadratic sequences (where the second difference is constant), you could use the formula: nth term = a+(n-1)d+0.5(n-1)(n-2)c where a is the first term, d is the difference between the first two terms and c is the second difference which is constant:

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

a=3 and the difference between 5 and 3 is 2 so d=2.

The first differences are 2, 3, 4, 5, ... so the second difference is 1 which is constant (this means it's a quadratic sequence). So c=1.

So the nth term is a 3 + 2(n-1) + 0.5(n-1)(n-2).

And you can simplify this to get the answer.


I don't really like teaching the formula, 1) It could be tricky to simplify the algebra and 2) You may get too used to using it and forget methods of substitution which are commonly asked at IGCSE.

For quadratic sequences (like the one above), I recommend the method in the final post on this page: https://www.xtremepapers.com/community/threads/mathematics-post-your-doubts-here.2565/page-162
but i think i dont have another option to get marks :)
 
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Here you go.
what does this mean The equation ()= has one solution when the line = intersects () at one point only. This happens approximately when <1.9 but we can choose any range so to be safe we will write <1.5 . from the attachment
 
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i need to know quickly cz my board is day after tomorrow
This is really lengthy and would take a lot of my time as i am having my boards too
i will try to summarize it
Take the midpoint of each range for example the first onw will be (0.5+0)/2 =0.25 this is for the first one take for all
and then use the formula fx/f
which means (0.25*8)+(o.75*27)+ and so on till the end and then you divide all this by 200 which is the f
this is how you find estimate of the mean
you have made a graph right?? to find median 200/2 =100
on the y axis is the cumulative frequency so 100 of that on x axis will be the answer
that is it! I hope i helped sorry about not explaining the whole thing as i a preparing too
 
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I keep getting PMs about this so I thought I'd send a general message:

I do not have access to Paper 4 until the exam starts. I know as much as all of you about it's content. An even if I did know something, I would not under any circumstances share the information.

So stop trying to cheat and focus on revising for the exam. If you have something to ask me, post it on one of the threads - you do not need to PM me.

(I will answer all questions that I haven't answered yet before tomorrow).
 
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in paper http://papers.xtremepapers.com/CIE/Cambridge%20IGCSE/Mathematics%20(0580)/0580_w11_qp_43.pdf
Q.10d i and ii,we have to draw that,which I did,and I have attached the picture of what I drew which i checked more than once here,now for finding least cost of boxes,I know that method of substitu
attachment
ting the points in the unshaded area with the 5x + 2y but do we have to choose and try EACH and every point in the unshaded area?as the question is only for one mark,also,if you take point 6.5,6.5 and subtitute in the formula you would get 45.5 which is less than 47,does that mean we can never take any numbers other than whole numbers while subsituting in these kind of inequality questions?
thank you!!
 
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