[JenniS]

Hi, another question, f(x)=3x/x+1 - x+7/x^2-1 show that f(x)=3 - 4/x-1

I'm normally good at these, but I can't show that! I keep getting 3x-7/x-1 HELP!!!
Thanks

[0range]

(Original post by JenniS)
Hi, another question, f(x)=3x/x+1 - x+7/x^2-1 show that f(x)=3 - 4/x-1

I'm normally good at these, but I can't show that! I keep getting 3x-7/x-1 HELP!!!
Thanks

You're right. You just haven't finished there, you just have to use long division then you get what they want. So with long division divide 3x-7 by x-1.

Once you've done that you get 3- 4/(x-1)

[JenniS]

(Original post by 0range)
You're right. You just haven't finished there, you just have to use long division then you get what they want. So with long division divide 3x-7 by x-1.

Once you've done that you get 3- 4/(x-1)

omg thanks! actually wouldn't have thought to do that oh dear. but it makes sense thanks!

[arnab]

can anyone integrate this for me please? I cant seem to be able to do it. Tried integrating it with the substitution method but i cant seem to get the right answer lol




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[0range]

Anyone think something similar to Q8 in the Jan 07 paper could come up again? I was literally staring at that question for like 15mins then just switched to examsolutions :P

Apparently less then 10% of the people sitting the exam got that right 0.0

(Original post by JenniS)
omg thanks! actually wouldn't have thought to do that oh dear. but it makes sense thanks!

You're welcome

[grazie]

(Original post by arnab)
can anyone integrate this for me please? I cant seem to be able to do it. Tried integrating it with the substitution method but i cant seem to get the right answer lol




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Yes, but this is a C4 question and should be on a C4 thread.

[masterhr1]

Anyone have a list of ALL the trigonometric identities we need for C3?

[reetkang]

(Original post by arnab)
Thanks......anyone else care to confirm this?

hey, u can get 2004 and 2005 papers from http://www.xtremepapers.com/papers/AQA/Maths/ this link..

[arnab]

(Original post by reetkang)
hey, u can get 2004 and 2005 papers from http://www.xtremepapers.com/papers/AQA/Maths/ this link..

its AQA

[arnab]

(Original post by masterhr1)
Anyone have a list of ALL the trigonometric identities we need for C3?

The ones that are not in the booklet as well

[grazie]

(Original post by arnab)
The ones that are not in the booklet as well

The summary sections of the trig chapters in the textbook gives all the trig identities needed. Personally, I think it easier to derive these from the ones provided in the Formula Book, rather than trying to remember them all. If you're do lots of trig questions they begin to stick anyway (for a while at least).

[0range]

I'm pretty much going to have to go bak to basics, and just work of the textbook, past papers are way too hard for some reason, I was flying through them 2 weeks ago, then I took a two week break, now I can barely do the first question on the freaking paper!!!

[Pi!]

Don't you just love trigonometry?

[MuffinMonster]

(Original post by 0range)
Anyone think something similar to Q8 in the Jan 07 paper could come up again? I was literally staring at that question for like 15mins then just switched to examsolutions :P

Apparently less then 10% of the people sitting the exam got that right 0.0





You're welcome

I was trying to see why the answer was like that for ages and then realised I read the question as arccos rather than arcsin, and then it was so clear all of a sudden...I feel stupid.

[101101]

Can somebody please explain Q8 IN JAN 07 paper? Iv tried examsolutions be he uses a cast diagram and I have never used / heard of his method?

[XxAmxX]

(Original post by 0range)
I'm pretty much going to have to go bak to basics, and just work of the textbook, past papers are way too hard for some reason, I was flying through them 2 weeks ago, then I took a two week break, now I can barely do the first question on the freaking paper!!!

Im with you!! Tried to sort my papers into topics....but i seem to be having to check stuff up on pretty much every question :/ And i just dont have the motivation to go through the entire book in a few days :/

[0range]

(Original post by XxAmxX)
Im with you!! Tried to sort my papers into topics....but i seem to be having to check stuff up on pretty much every question :/ And i just dont have the motivation to go through the entire book in a few days :/

I know exactly how you feel!, I've already done that once on my own, and am definitely not doing that again. Atm I'm just doing the review exercises in my book and seeing how they do it on the CD, it does help but the questions on the papers just seem much harder :s

[masterhr1]

is an x⁴ equation a parabola like x² or is it something else?

[grazie]

(Original post by 101101)
Can somebody please explain Q8 IN JAN 07 paper? Iv tried examsolutions be he uses a cast diagram and I have never used / heard of his method?

Do you mean 8 ii) part a) and b)? I think 8 i) is fairly standard. Do you know that



It's the same for cos and tan.

[grazie]

(Original post by masterhr1)
is an x⁴ equation a parabola like x² or is it something else?

It's similar in shape, but it's not a parabola.