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Original post by justinawe
Just googled "telescoping series", and realised that's exactly the same thing I did :colonhash:


Telescoping series is (I think) the popular name in America. I've always just called it the method of differences.
Original post by DJMayes
Telescoping series is (I think) the popular name in America. I've always just called it the method of differences.


Ah. iirc, they call the trapezium rule the "trapezoidal rule" or something funky like that :colone:
S1 shall be obliterated :h:

Although, some of these probability ones throw me off a little :s-smilie:

Why is:

P(A|AnB) = P(A)/P(AnB)?????

I thought it should be:

P(A n AnB)/P(AnB)
Has anyone got access to the edexcel emporium ... like all the resources on there??

Ryan
Original post by L'Evil Fish
S1 shall be obliterated :h:

Although, some of these probability ones throw me off a little :s-smilie:

Why is:

P(A|AnB) = P(A)/P(AnB)?????

I thought it should be:

P(A n AnB)/P(AnB)


What you've written there is "The probability that event A happens given that event A and B happen" which is quite clearly 1.
(edited 10 years ago)
Original post by L'Evil Fish
S1 shall be obliterated :h:

Although, some of these probability ones throw me off a little :s-smilie:

Why is:

P(A|AnB) = P(A)/P(AnB)?????

I thought it should be:

P(A n AnB)/P(AnB)


And what is the probability A intersects AnB, why its the probability of A
Original post by DJMayes
What you've written there is "The probability that event A happens given that event A and B happens" which is quite clearly 1.


Okay, bad example... I copied it wrong. But why wasn't it the probability of both happening over the second half happening?:s-smilie:
Original post by L'Evil Fish
Okay, bad example... I copied it wrong. But why wasn't it the probability of both happening over the second half happening?:s-smilie:


It is. The rule is:

P(AB)=P(AB)P(B) P(A|B) = \dfrac{P(A \cap B)}{P(B)}

There is a second formula for conditional probability (Derived from this one) but it is not one you need to know.
Now that I'm at home could someone tell me which page the question was on as I can't remember myself :-/

I'm going to fight for my place now and not give in just because of one certain outcome, Warwick will be begging for me to stay after my 4 years! :biggrin:


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Original post by MathsNerd1
Now that I'm at home could someone tell me which page the question was on as I can't remember myself :-/

I'm going to fight for my place now and not give in just because of one certain outcome, Warwick will be begging for me to stay after my 4 years! :biggrin:


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Here:


Original post by Felix Felicis
Here's a question :colone:

Simplify (with justification :rolleyes: ) r=1nr(r+1)!\displaystyle \sum_{r=1}^{n} \frac{r}{(r+1)!}
Original post by MathsNerd1
Now that I'm at home could someone tell me which page the question was on as I can't remember myself :-/

I'm going to fight for my place now and not give in just because of one certain outcome, Warwick will be begging for me to stay after my 4 years! :biggrin:


Posted from TSR Mobile


Good, stay positive! :smile:
I know this might be a stupid question but I can't get my head around it now. :tongue:
If I get something like (2x+3)/(x-1)
How the hell am I supposed to know how to express it in the form
a+b/(x-1)
(a, b are constants)? :biggrin:
Original post by justinawe
Here:


Okay thanks, let me just do my first C3 paper and then I'll try this out, nothing's going to keep me from achieving what I know I deserve! :biggrin:
Original post by purplemind
I know this might be a stupid question but I can't get my head around it now. :tongue:
If I get something like (2x+3)/(x-1)
How the hell am I supposed to know how to express it in the form
a+b/(x-1)
(a, b are constants)? :biggrin:

2x+3x1=2x2+2+3x1=2x2x1+5x1\displaystyle \frac{2x+3}{x-1} = \frac{2x - 2 +2 + 3}{x-1} = \frac{2x-2}{x-1} + \frac{5}{x-1} :wink:
Original post by Zaphod77
Good, stay positive! :smile:


I'm eager to hear your response about this morning.
Original post by MAyman12
If the final answer is wrong, you must lose some A1 marks along the way.
I had the same problem with M1 this May.:frown: I feel you mate.


Hmm...if that's the case then what is Error carried forward? It seems that you would get method marks anyway regardless of whether you got answers wrong in the previous part or elsewhere.
Original post by MathsNerd1
I'm eager to hear your response about this morning.


Yeah, I really want to talk about it! I'm tempted to stay up to midnight to talk, but I'm not very good at keeping awake :tongue: I'm going to try though, or set an alarm for midnight, I'd be interested to find out how everyone else found it - only 3 people sat the exam in my school!
Original post by DJMayes
It is. The rule is:

P(AB)=P(AB)P(B) P(A|B) = \dfrac{P(A \cap B)}{P(B)}

There is a second formula for conditional probability (Derived from this one) but it is not one you need to know.


So is the m/s wrong... Or :s-smilie:

Another issue, when can I use tables? And how do they work?:colondollar:
Original post by Felix Felicis
2x+3x1=2x2+2+3x1=2x2x1+5x1\displaystyle \frac{2x+3}{x-1} = \frac{2x - 2 +2 + 3}{x-1} = \frac{2x-2}{x-1} + \frac{5}{x-1} :wink:

Oh, thanks.
So it is the only way to do it? :biggrin:
(I should start copying notes from lessons I miss :teehee:)
Original post by purplemind
Oh, thanks.
So it is the only way to do it? :biggrin:
(I should start copying notes from lessons I miss :teehee:)

Noooo, algebraic long division also works but if you feel comfortable, this method's marginally quicker :biggrin:

Original post by L'Evil Fish
So is the m/s wrong... Or :s-smilie:

Another issue, when can I use tables? And how do they work?:colondollar:

Where is your god now :colone:

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