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A month into A2 knowing **** all about Maths

Want a B in A2 maths but that seems unlikely after scraping a U in a class test. I can't seem to get my head around topics in C3, especially trigonometry. I know the formulas but I don't know which cos2x formula to use when proving identities. Please provide advice to a lost confused kid

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Reply 1
Original post by Mesosleepy
Want a B in A2 maths but that seems unlikely after scraping a U in a class test. I can't seem to get my head around topics in C3, especially trigonometry. I know the formulas but I don't know which cos2x formula to use when proving identities. Please provide advice to a lost confused kid


C3 and C4 take a while to get your head around
Reply 2
Original post by Andy98
C3 and C4 take a while to get your head around


How long did it take for you?
You'll be fine. It took me a long time to get used to C3 trig but it gets better with practice. Just learn the formulas and do as many questions as you can get your hands on.

When it comes to using the cos2x formula, look at whether the question involves sin^2x or cos^2x. That's the big hint to figuring out which formula to use :smile:
Exam solutions + questions + effort = success
In my classes I just stare at my maths teachers bald head and it inspires me to get the right answer for some reason.
C3 is all about practice, C4 as well.

After a while you'll get the hang of it:

Right, which side looks more complicated/which should I start with?

Can I apply any identities I know? Factor out anything? Combine fractions?

...and eventually you get to the other side. There may or may not be a hint on the other side as to what you need to do.

It doesn't hurt to think about each cos2x identity, perhaps trying each one but eventually you may be able to so it in our head and see which one outputs something that is actually useful.
Original post by Mesosleepy
Want a B in A2 maths but that seems unlikely after scraping a U in a class test. I can't seem to get my head around topics in C3, especially trigonometry. I know the formulas but I don't know which cos2x formula to use when proving identities. Please provide advice to a lost confused kid


You could always try asking your teacher for extra help or using any revision videos you can find. Also how can you scrape a U?
Reply 8
Original post by Mesosleepy
Want a B in A2 maths but that seems unlikely after scraping a U in a class test. I can't seem to get my head around topics in C3, especially trigonometry. I know the formulas but I don't know which cos2x formula to use when proving identities. Please provide advice to a lost confused kid


C3 trig questions are mastered by practice and consequent assimilation of many different themes in questions. Go through examples and try to understand why they choose to use certain identities and do certain manipulations. If one formula doesn't work, try a different one; it will help you get a feel for what is the right and wrong approach and you should get there in the end if you try enough ideas.. and don't forget there is always algebraic trickery to be done, it might not be as pleasant when you're working with a load of trig as opposed to x and y but the same possibilities are there.
Reply 9
Use the website http://www.physicsandmathstutor.com. I found this very helpful. You can find many things on there like Past papers, revision notes and even topic based exam questions. You just need to do practice and lots of revision. And who knows u might get even better grade than B. Good luck.


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Reply 10
Original post by Kaddy_Dee
You'll be fine. It took me a long time to get used to C3 trig but it gets better with practice. Just learn the formulas and do as many questions as you can get your hands on.

When it comes to using the cos2x formula, look at whether the question involves sin^2x or cos^2x. That's the big hint to figuring out which formula to use :smile:


Ok I try to follow your advice starting tomorrow
Reply 11
Original post by TheSexyApple
In my classes I just stare at my maths teachers bald head and it inspires me to get the right answer for some reason.


I guess I will fail since my teacher has hair
Reply 12
Original post by Mesosleepy
How long did it take for you?


About two months; but I did FM
Reply 13
Original post by Questioner1234
You could always try asking your teacher for extra help or using any revision videos you can find. Also how can you scrape a U?


zilch
Reply 14
Original post by Andy98
About two months; but I did FM


C3 and C4 in two months, holy ****. What did you do?, what resources you use?
Reply 15
Original post by Mesosleepy
C3 and C4 in two months, holy ****. What did you do?, what resources you use?


I dunno, just did the homework college set
In all honesty, it takes a lot of effort to be any good. If you don't want to spend a tonne of your time doing maths, why do it? I'm guessing it's compulsory for a course or something?
My friends always think I'm some genius that somehow 'gets' all of this stuff, but whilst they're sat twiddling their thumbs, memorising formulae and definitions, I actually spend time learning why these things work, how to get the formula, experimenting with new ideas, reading online about extra stuff, learning topics in advance, learning extra modules to improve my overall understanding, and so on. Anyone can be good if they put the time in.

Once you've got the understanding down, it's a matter of not f***king up, just do enough questions until you realise all of the stupid mistakes you make and/or the misconceptions you had about certain ideas to prevent the stupid systematic errors.

(for example, when doing complex numbers last year, I thought that if z=a+ibz=a2+(ib)2=a2b2 z = a + ib \Rightarrow |z| = a^2 + (ib)^2 = a^2 - b^2, it wasn't until I read about eiθe^{i\theta}, Euler's formula and polar coordinates during the holidays when I realised that it's thought of as a radius in the complex plane instead of some arbitrary weird number; I can't remember if that was on the exam though) (just realised you probably haven't done complex numbers, nm haha)

If you want to be any good, spending more time on it is seriously the only thing you can do. If you read ahead, it might help you if you get an understanding of more difficult stuff first and then when you look back, it looks like a piece of p*ss; or it might not help at all. My advice to you would be to try and study with someone that has a better understanding than you do (maybe a further maths person). Meet up in your free time and revise together. Teachers typically won't have the time to help with everything you need, but if you get a 'study buddy' [as my physics teacher calls it], you'll both be benefiting from it and you can pester them with everything that you don't understand.
Reply 17
i'm having the same problem with maths this year, i managed to get an A in maths AS last year (Low A in C1, C2 and S1), and I'm really worried about this year. I have to get an A in maths overall as i want to study computer science at uni, and this is required. So does anyone know roughly what grade i have to get in A2 maths (C3,C4 and S2) in order to make sure my overall maths a level grade is an A??

and anyone have any tips on how to understand the stuff in C3? I'm the kind of person where once i fully fully get a concept, i'll be able to practice it and i'll be fine, i just really struggle with actually understanding the stuff so i can't really do any of the questions. I get the basic concepts, i just can't seem to apply any of it. anyone got any suggestions for how to grasp it so i can start practicing??? or anyone have any good c3 notes?
Reply 18
Original post by SSD07
i'm having the same problem with maths this year, i managed to get an A in maths AS last year (Low A in C1, C2 and S1), and I'm really worried about this year. I have to get an A in maths overall as i want to study computer science at uni, and this is required. So does anyone know roughly what grade i have to get in A2 maths (C3,C4 and S2) in order to make sure my overall maths a level grade is an A??

and anyone have any tips on how to understand the stuff in C3? I'm the kind of person where once i fully fully get a concept, i'll be able to practice it and i'll be fine, i just really struggle with actually understanding the stuff so i can't really do any of the questions. I get the basic concepts, i just can't seem to apply any of it. anyone got any suggestions for how to grasp it so i can start practicing??? or anyone have any good c3 notes?


With a low A last year you need to average a high B this year (you need a total of 480/600 UMS; from this and your AS UMS you can figure out exactly what you need)

If you're doing edexcel the textbook is not bad. You've probably been told about the examsolutions website before but if not then it's a great resource; the videos can sometimes be a little too slow but it's very helpful generally. As I said to the OP I think, you need to work through examples and understand how the concepts are being applied. There must be simpler textbook questions, that relate quite obviously to examples, you can do, and then once you're well versed in them maybe move on to exam-style questions. Is there anything in particular that challenges you more? As usually it seems trig proofs and function, mainly domain and range, stuff are the main issues people have with C3, with differentiation being sometimes problematic as well, whereas most are happier with the algebra, iterations, exponentials, absolute value stuff etc.
Original post by Callum Scott
I thought that if z=a+ibz=a2+(ib)2=a2b2 z = a + ib \Rightarrow |z| = a^2 + (ib)^2 = a^2 - b^2


Just to be clear, you realise this isn't correct now? z=a+ibz=a2+b2z = a+ib \Rightarrow |z| = \sqrt{a^2 + b^2}. If you're working in cartesian form, the easiest way to think about it is as the distance from the origin or equivalently the modulus of the position vector of the point represented by z.

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